This handbook is a guide to ordinal theory. Ordinal theory concerns itself with gros, giving them individual identities and allowing them to be tracked, transferred, and imbued with meaning.

Gros, not groestlcoin, are the atomic, native currency of the Groestlcoin network. One groestlcoin can be sub-divided into 100,000,000 gros, but no further.

Ordinal theory does not require a sidechain or token aside from Groestlcoin, and can be used without any changes to the Groestlcoin network. It works right now.

Ordinal theory imbues gros with numismatic value, allowing them to be collected and traded as curios.

Individual gros can be inscribed with arbitrary content, creating unique Groestlcoin-native digital artifacts that can be held in Groestlcoin wallets and transferred using Groestlcoin transactions. Inscriptions are as durable, immutable, secure, and decentralized as Groestlcoin itself.

Other, more unusual use-cases are possible: off-chain colored-coins, public key infrastructure with key rotation, a decentralized replacement for the DNS. For now though, such use-cases are speculative, and exist only in the minds of fringe ordinal theorists.

For more details on ordinal theory, see the overview.

For more details on inscriptions, see inscriptions.

When you're ready to get your hands dirty, a good place to start is with inscriptions, a curious species of digital artifact enabled by ordinal theory.

Ordinal Theory Overview

Ordinals are a numbering scheme for gros that allows tracking and transferring individual gros. These numbers are called ordinal numbers. Gros are numbered in the order in which they're mined, and transferred from transaction inputs to transaction outputs first-in-first-out. Both the numbering scheme and the transfer scheme rely on order, the numbering scheme on the order in which gros are mined, and the transfer scheme on the order of transaction inputs and outputs. Thus the name, ordinals.

Technical details are available in the BIP.

Ordinal theory does not require a separate token, another blockchain, or any changes to Groestlcoin. It works right now.

Ordinal numbers have a few different representations:

  • Integer notation: 2099994106992659 The ordinal number, assigned according to the order in which the gro was mined.

  • Decimal notation: 3891094.16797 The first number is the block height in which the gro was mined, the second the offset of the gro within the block.

  • Degree notation: 3°111094′214″16797‴. We'll get to that in a moment.

  • Percentile notation: 99.99971949060254% . The gro's position in Groestlcoin's supply, expressed as a percentage.

  • Name: satoshi. An encoding of the ordinal number using the characters a through z.

Arbitrary assets, such as NFTs, security tokens, accounts, or stablecoins can be attached to gros using ordinal numbers as stable identifiers.

Ordinals is an open-source project, developed on GitHub. The project consists of a BIP describing the ordinal scheme, an index that communicates with a Groestlcoin Core node to track the location of all gros, a wallet that allows making ordinal-aware transactions, a block explorer for interactive exploration of the blockchain, functionality for inscribing gros with digital artifacts, and this manual.


Humans are collectors, and since gros can now be tracked and transferred, people will naturally want to collect them. Ordinal theorists can decide for themselves which gros are rare and desirable, but there are some hints…

Groestlcoin has periodic events, some frequent, some more uncommon, and these naturally lend themselves to a system of rarity. These periodic events are:

  • Blocks: A new block is mined approximately every 1 minute, from now until the end of time.

  • Difficulty adjustments: Every 2016 blocks, or approximately every 1.5 days, the Groestlcoin network responds to changes in hashrate by adjusting the difficulty target which blocks must meet in order to be accepted.

  • Halvings: Every 1,050,000 blocks.

  • Cycles: Every 6 * 1,050,000 blocks.

This gives us the following rarity levels:

  • common: Any gro that is not the first gro of its block
  • uncommon: The first gro of each block
  • rare: The first gro of each difficulty adjustment period
  • epic: The first gro of each halving epoch
  • legendary: The first gro of each cycle
  • mythic: The first gro of the genesis block

Which brings us to degree notation, which unambiguously represents an ordinal number in a way that makes the rarity of a gro easy to see at a glance:

│ │ │ ╰─ Index of gro in the block
│ │ ╰─── Index of block in difficulty adjustment period
│ ╰───── Index of block in halving epoch
╰─────── Cycle, numbered starting from 0

Ordinal theorists often use the terms "hour", "minute", "second", and "third" for A, B, C, and D, respectively.

Now for some examples. This gro is common:

│ │ │ ╰─ Not first gro in block
│ │ ╰─── Not first block in difficulty adjustment period
│ ╰───── Not first block in halving epoch
╰─────── Second cycle

This gro is uncommon:

│ │ │ ╰─ First gro in block
│ │ ╰─── Not first block in difficulty adjustment period
│ ╰───── Not first block in halving epoch
╰─────── Second cycle

This gro is rare:

│ │ │ ╰─ First gro in block
│ │ ╰─── First block in difficulty adjustment period
│ ╰───── Not the first block in halving epoch
╰─────── Second cycle

This gro is epic:

│ │ │ ╰─ First gro in block
│ │ ╰─── Not first block in difficulty adjustment period
│ ╰───── First block in halving epoch
╰─────── Second cycle

This gro is legendary:

│ │ │ ╰─ First gro in block
│ │ ╰─── First block in difficulty adjustment period
│ ╰───── First block in halving epoch
╰─────── Second cycle

And this gro is mythic:

│ │ │ ╰─ First gro in block
│ │ ╰─── First block in difficulty adjustment period
│ ╰───── First block in halving epoch
╰─────── First cycle

If the block offset is zero, it may be omitted. This is the uncommon gro from above:

│ │ ╰─ Not first block in difficulty adjustment period
│ ╰─── Not first block in halving epoch
╰───── Second cycle

Rare Gro Supply

Total Supply

  • common: 10.4 quadrillion
  • uncommon: 6,929,999
  • rare: 3437
  • epic: 32
  • legendary: 5
  • mythic: 1

Current Supply

  • common: 8.3 quadrillion
  • uncommon: 745,855
  • rare: 369
  • epic: 3
  • legendary: 0
  • mythic: 1

At the moment, even uncommon gros are quite rare. As of this writing, 745,855 uncommon gros have been mined - one per 25.6 groestlcoin in circulation.


Each gro has a name, consisting of the letters A through Z, that get shorter the further into the future the gro was mined. They could start short and get longer, but then all the good, short names would be trapped in the unspendable genesis block.

As an example, 1905530482684727°'s name is "iaiufjszmoba". The name of the last gro to be mined is "a". Every combination of 10 characters or less is out there, or will be out there, someday.


Gros may be prized for reasons other than their name or rarity. This might be due to a quality of the number itself, like having an integer square or cube root. Or it might be due to a connection to a historical event, such as gros from block 1,439,424, the block in which SegWit activated, or 10499999999999999°, the last gro that will ever be mined.

Such gros are termed "exotic". Which gros are exotic and what makes them so is subjective. Ordinal theorists are encouraged to seek out exotics based on criteria of their own devising.


Gros can be inscribed with arbitrary content, creating Groestlcoin-native digital artifacts. Inscribing is done by sending the gro to be inscribed in a transaction that reveals the inscription content on-chain. This content is then inextricably linked to that gro, turning it into an immutable digital artifact that can be tracked, transferred, hoarded, bought, sold, lost, and rediscovered.


Whether or not ordinals are of interest to NFT archaeologists is an open question! Ordinals were in fact created by Gruve-P in 2014 when he mined the Groestlcoin genesis block. In this sense, ordinals, and especially early ordinals, are certainly of historical interest.

Digital Artifacts

Imagine a physical artifact. A rare coin, say, held safe for untold years in the dark, secret clutch of a Viking hoard, now dug from the earth by your grasping hands. It…

…has an owner. You. As long as you keep it safe, nobody can take it from you.

…is complete. It has no missing parts.

…can only be changed by you. If you were a trader, and you made your way to 18th century China, none but you could stamp it with your chop-mark.

…can only be disposed of by you. The sale, trade, or gift is yours to make, to whomever you wish.

What are digital artifacts? Simply put, they are the digital equivalent of physical artifacts.

For a digital thing to be a digital artifact, it must be like that coin of yours:

  • Digital artifacts can have owners. A number is not a digital artifact, because nobody can own it.

  • Digital artifacts are complete. An NFT that points to off-chain content on IPFS or Arweave is incomplete, and thus not a digital artifact.

  • Digital artifacts are permissionless. An NFT which cannot be sold without paying a royalty is not permissionless, and thus not a digital artifact.

  • Digital artifacts are uncensorable. Perhaps you can change a database entry on a centralized ledger today, but maybe not tomorrow, and thus one cannot be a digital artifact.

  • Digital artifacts are immutable. An NFT with an upgrade key is not a digital artifact.

The definition of a digital artifact is intended to reflect what NFTs should be, sometimes are, and what inscriptions always are, by their very nature.


Inscriptions inscribe gros with arbitrary content, creating groestlcoin-native digital artifacts, more commonly known as NFTs. Inscriptions do not require a sidechain or separate token.

These inscribed gros can then be transferred using groestlcoin transactions, sent to groestlcoin addresses, and held in groestlcoin UTXOs. These transactions, addresses, and UTXOs are normal groestlcoin transactions, addresses, and UTXOS in all respects, with the exception that in order to send individual gros, transactions must control the order and value of inputs and outputs according to ordinal theory.

The inscription content model is that of the web. An inscription consists of a content type, also known as a MIME type, and the content itself, which is a byte string. This allows inscription content to be returned from a web server, and for creating HTML inscriptions that use and remix the content of other inscriptions.

Inscription content is entirely on-chain, stored in taproot script-path spend scripts. Taproot scripts have very few restrictions on their content, and additionally receive the witness discount, making inscription content storage relatively economical.

Since taproot script spends can only be made from existing taproot outputs, inscriptions are made using a two-phase commit/reveal procedure. First, in the commit transaction, a taproot output committing to a script containing the inscription content is created. Second, in the reveal transaction, the output created by the commit transaction is spent, revealing the inscription content on-chain.

Inscription content is serialized using data pushes within unexecuted conditionals, called "envelopes". Envelopes consist of an OP_FALSE OP_IF … OP_ENDIF wrapping any number of data pushes. Because envelopes are effectively no-ops, they do not change the semantics of the script in which they are included, and can be combined with any other locking script.

A text inscription containing the string "Hello, world!" is serialized as follows:

  OP_PUSH "ord"
  OP_PUSH "text/plain;charset=utf-8"
  OP_PUSH "Hello, world!"

First the string ord is pushed, to disambiguate inscriptions from other uses of envelopes.

OP_PUSH 1 indicates that the next push contains the content type, and OP_PUSH 0indicates that subsequent data pushes contain the content itself. Multiple data pushes must be used for large inscriptions, as one of taproot's few restrictions is that individual data pushes may not be larger than 520 bytes.

The inscription content is contained within the input of a reveal transaction, and the inscription is made on the first gro of its input. This gro can then be tracked using the familiar rules of ordinal theory, allowing it to be transferred, bought, sold, lost to fees, and recovered.


The data model of inscriptions is that of a HTTP response, allowing inscription content to be served by a web server and viewed in a web browser.


Inscriptions may include fields before an optional body. Each field consists of two data pushes, a tag and a value.

Currently, the only defined field is content-type, with a tag of 1, whose value is the MIME type of the body.

The beginning of the body and end of fields is indicated with an empty data push.

Unrecognized tags are interpreted differently depending on whether they are even or odd, following the "it's okay to be odd" rule used by the Lightning Network.

Even tags are used for fields which may affect creation, initial assignment, or transfer of an inscription. Thus, inscriptions with unrecognized even fields must be displayed as "unbound", that is, without a location.

Odd tags are used for fields which do not affect creation, initial assignment, or transfer, such as additional metadata, and thus are safe to ignore.

Inscription IDs

The inscriptions are contained within the inputs of a reveal transaction. In order to uniquely identify them they are assigned an ID of the form:


The part in front of the i is the transaction ID (txid) of the reveal transaction. The number after the i defines the index (starting at 0) of new inscriptions being inscribed in the reveal transaction.

Inscriptions can either be located in different inputs, within the same input or a combination of both. In any case the ordering is clear, since a parser would go through the inputs consecutively and look for all inscription envelopes.

InputInscription CountIndices
02i0, i1
23i3, i4, i5


HTML and SVG inscriptions are sandboxed in order to prevent references to off-chain content, thus keeping inscriptions immutable and self-contained.

This is accomplished by loading HTML and SVG inscriptions inside iframes with the sandbox attribute, as well as serving inscription content with Content-Security-Policy headers.


Inscriptions may include CBOR metadata, stored as data pushes in fields with tag 5. Since data pushes are limited to 520 bytes, metadata longer than 520 bytes must be split into multiple tag 5 fields, which will then be concatenated before decoding.

Metadata is human readable, and all metadata will be displayed to the user with its inscription. Inscribers are encouraged to consider how metadata will be displayed, and make metadata concise and attractive.

Metadata is rendered to HTML for display as follows:

  • null, true, false, numbers, floats, and strings are rendered as plain text.
  • Byte strings are rendered as uppercase hexadecimal.
  • Arrays are rendered as <ul> tags, with every element wrapped in <li> tags.
  • Maps are rendered as <dl> tags, with every key wrapped in <dt> tags, and every value wrapped in <dd> tags.
  • Tags are rendered as the tag , enclosed in a <sup> tag, followed by the value.

CBOR is a complex spec with many different data types, and multiple ways of representing the same data. Exotic data types, such as tags, floats, and bignums, and encoding such as indefinite values, may fail to display correctly or at all. Contributions to ord to remedy this are welcome.


Since CBOR is not human readable, in these examples it is represented as JSON. Keep in mind that this is only for these examples, and JSON metadata will not be displayed correctly.

The metadata {"foo":"bar","baz":[null,true,false,0]} would be included in an inscription as:

    OP_PUSH 0x05 OP_PUSH '{"foo":"bar","baz":[null,true,false,0]}'

And rendered as:


Metadata longer than 520 bytes must be split into multiple fields:

    OP_PUSH 0x05 OP_PUSH '{"very":"long","metadata":'
    OP_PUSH 0x05 OP_PUSH '"is","finally":"done"}'

Which would then be concatinated into {"very":"long","metadata":"is","finally":"done"}.


The owner of an inscription can create child inscriptions, trustlessly establishing the provenance of those children on-chain as having been created by the owner of the parent inscription. This can be used for collections, with the children of a parent inscription being members of the same collection.

Children can themselves have children, allowing for complex hierarchies. For example, an artist might create an inscription representing themselves, with sub inscriptions representing collections that they create, with the children of those sub inscriptions being items in those collections.


To create a child inscription C with parent inscription P:

  • Create an inscribe transaction T as usual for C.
  • Spend the parent P in one of the inputs of T.
  • Include tag 3, i.e. OP_PUSH 3, in C, with the value of the serialized binary inscription ID of P, serialized as the 32-byte TXID, followed by the four-byte little-endian INDEX, with trailing zeroes omitted.

NB The bytes of a groestlcoin transaction ID are reversed in their text representation, so the serialized transaction ID will be in the opposite order.


An example of a child inscription of 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1fi0:

  OP_PUSH "ord"
  OP_PUSH "text/plain;charset=utf-8"
  OP_PUSH 0x1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100
  OP_PUSH "Hello, world!"

Note that the value of tag 3 is binary, not hex, and that for the child inscription to be recognized as a child, 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1fi0 must be spent as one of the inputs of the inscribe transaction.

Example encoding of inscription ID 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1fi255:

  OP_PUSH 0x1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100ff

And of inscription ID 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1fi256:

  OP_PUSH 0x1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a090807060504030201000001


The tag 3 is used because it is the first available odd tag. Unrecognized odd tags do not make an inscription unbound, so child inscriptions would be recognized and tracked by old versions of ord.

A collection can be closed by burning the collection's parent inscription, which guarantees that no more items in the collection can be issued.


An important exception to sandboxing is recursion: access to ord's /content endpoint is permitted, allowing inscriptions to access the content of other inscriptions by requesting /content/<INSCRIPTION_ID>.

This has a number of interesting use-cases:

  • Remixing the content of existing inscriptions.

  • Publishing snippets of code, images, audio, or stylesheets as shared public resources.

  • Generative art collections where an algorithm is inscribed as JavaScript, and instantiated from multiple inscriptions with unique seeds.

  • Generative profile picture collections where accessories and attributes are inscribed as individual images, or in a shared texture atlas, and then combined, collage-style, in unique combinations in multiple inscriptions.

A few other endpoints that inscriptions may access are the following:

  • /blockheight: latest block height.
  • /blockhash: latest block hash.
  • /blockhash/<HEIGHT>: block hash at given block height.
  • /blocktime: UNIX time stamp of latest block.


In order to make an inscription on a sat other than the first of its input, a zero-based integer, called the "pointer", can be provided with tag 2, causing the inscription to be made on the sat at the given position in the outputs. If the pointer is equal to or greater than the number of total sats in the outputs of the inscribe transaction, it is ignored, and the inscription is made as usual. The value of the pointer field is a little endian integer, with trailing zeroes ignored.

An even tag is used, so that old versions of ord consider the inscription to be unbound, instead of assigning it, incorrectly, to the first sat.

This can be used to create multiple inscriptions in a single transaction on different sats, when otherwise they would be made on the same sat.


An inscription with pointer 255:

  OP_PUSH "ord"
  OP_PUSH "text/plain;charset=utf-8"
  OP_PUSH 0xff
  OP_PUSH "Hello, world!"

An inscription with pointer 256:

  OP_PUSH "ord"
  OP_PUSH "text/plain;charset=utf-8"
  OP_PUSH 0x0001
  OP_PUSH "Hello, world!"

An inscription with pointer 256, with trailing zeroes, which are ignored:

  OP_PUSH "ord"
  OP_PUSH "text/plain;charset=utf-8"
  OP_PUSH 0x000100
  OP_PUSH "Hello, world!"

Ordinal Theory FAQ

What is ordinal theory?

Ordinal theory is a protocol for assigning serial numbers to gros, the smallest subdivision of a groestlcoin, and tracking those gros as they are spent by transactions.

These serial numbers are large numbers, like this 804766073970493. Every gro, which is ¹⁄₁₀₀₀₀₀₀₀₀ of a groestlcoin, has an ordinal number.

Does ordinal theory require a side chain, a separate token, or changes to Groestlcoin?

Nope! Ordinal theory works right now, without a side chain, and the only token needed is groestlcoin itself.

What is ordinal theory good for?

Collecting, trading, and scheming. Ordinal theory assigns identities to individual gros, allowing them to be individually tracked and traded, as curios and for numismatic value.

Ordinal theory also enables inscriptions, a protocol for attaching arbitrary content to individual gros, turning them into groestlcoin-native digital artifacts.

How does ordinal theory work?

Ordinal numbers are assigned to gros in the order in which they are mined. The first gro in the first block has ordinal number 0, the second has ordinal number 1, and the last gro of the first block has ordinal number 4,999,999,999.

Gros live in outputs, but transactions destroy outputs and create new ones, so ordinal theory uses an algorithm to determine how gros hop from the inputs of a transaction to its outputs.

Fortunately, that algorithm is very simple.

Gros transfer in first-in-first-out order. Think of the inputs to a transaction as being a list of gros, and the outputs as a list of slots, waiting to receive a gro. To assign input gros to slots, go through each gro in the inputs in order, and assign each to the first available slot in the outputs.

Let's imagine a transaction with three inputs and two outputs. The inputs are on the left of the arrow and the outputs are on the right, all labeled with their values:

[2] [1] [3] → [4] [2]

Now let's label the same transaction with the ordinal numbers of the gros that each input contains, and question marks for each output slot. Ordinal numbers are large, so let's use letters to represent them:

[a b] [c] [d e f] → [? ? ? ?] [? ?]

To figure out which gro goes to which output, go through the input gros in order and assign each to a question mark:

[a b] [c] [d e f] → [a b c d] [e f]

What about fees, you might ask? Good question! Let's imagine the same transaction, this time with a two gro fee. Transactions with fees send more gros in the inputs than are received by the outputs, so to make our transaction into one that pays fees, we'll remove the second output:

[2] [1] [3] → [4]

The gros e and f now have nowhere to go in the outputs:

[a b] [c] [d e f] → [a b c d]

So they go to the miner who mined the block as fees. The BIP has the details, but in short, fees paid by transactions are treated as extra inputs to the coinbase transaction, and are ordered how their corresponding transactions are ordered in the block. The coinbase transaction of the block might look like this:

[SUBSIDY] [e f] → [SUBSIDY e f]

Where can I find the nitty-gritty details?

The BIP!

Why are gro inscriptions called "digital artifacts" instead of "NFTs"?

An inscription is an NFT, but the term "digital artifact" is used instead, because it's simple, suggestive, and familiar.

The phrase "digital artifact" is highly suggestive, even to someone who has never heard the term before. In comparison, NFT is an acronym, and doesn't provide any indication of what it means if you haven't heard the term before.

Additionally, "NFT" feels like financial terminology, and the both word "fungible" and sense of the word "token" as used in "NFT" is uncommon outside of financial contexts.

How do gro inscriptions compare to…

Ethereum NFTs?

Inscriptions are always immutable.

There is simply no way to for the creator of an inscription, or the owner of an inscription, to modify it after it has been created.

Ethereum NFTs can be immutable, but many are not, and can be changed or deleted by the NFT contract owner.

In order to make sure that a particular Ethereum NFT is immutable, the contract code must be audited, which requires detailed knowledge of the EVM and Solidity semantics.

It is very hard for a non-technical user to determine whether or not a given Ethereum NFT is mutable or immutable, and Ethereum NFT platforms make no effort to distinguish whether an NFT is mutable or immutable, and whether the contract source code is available and has been audited.

Inscription content is always on-chain.

There is no way for an inscription to refer to off-chain content. This makes inscriptions more durable, because content cannot be lost, and scarcer, because inscription creators must pay fees proportional to the size of the content.

Some Ethereum NFT content is on-chain, but much is off-chain, and is stored on platforms like IPFS or Arweave, or on traditional, fully centralized web servers. Content on IPFS is not guaranteed to continue to be available, and some NFT content stored on IPFS has already been lost. Platforms like Arweave rely on weak economic assumptions, and will likely fail catastrophically when these economic assumptions are no longer met. Centralized web servers may disappear at any time.

It is very hard for a non-technical user to determine where the content of a given Ethereum NFT is stored.

Inscriptions are much simpler.

Ethereum NFTs depend on the Ethereum network and virtual machine, which are highly complex, constantly changing, and which introduce changes via backwards-incompatible hard forks.

Inscriptions, on the other hand, depend on the Groestlcoin blockchain, which is relatively simple and conservative, and which introduces changes via backwards-compatible soft forks.

Inscriptions are more secure.

Inscriptions inherit Groestlcoin's transaction model, which allow a user to see exactly which inscriptions are being transferred by a transaction before they sign it. Inscriptions can be offered for sale using partially signed transactions, which don't require allowing a third party, such as an exchange or marketplace, to transfer them on the user's behalf.

By comparison, Ethereum NFTs are plagued with end-user security vulnerabilities. It is commonplace to blind-sign transactions, grant third-party apps unlimited permissions over a user's NFTs, and interact with complex and unpredictable smart contracts. This creates a minefield of hazards for Ethereum NFT users which are simply not a concern for ordinal theorists.

Inscriptions are scarcer.

Inscriptions require groestlcoin to mint, transfer, and store. This seems like a downside on the surface, but the raison d'etre of digital artifacts is to be scarce and thus valuable.

Ethereum NFTs, on the other hand, can be minted in virtually unlimited qualities with a single transaction, making them inherently less scarce, and thus, potentially less valuable.

Inscriptions do not pretend to support on-chain royalties.

On-chain royalties are a good idea in theory but not in practice. Royalty payment cannot be enforced on-chain without complex and invasive restrictions. The Ethereum NFT ecosystem is currently grappling with confusion around royalties, and is collectively coming to grips with the reality that on-chain royalties, which were messaged to artists as an advantage of NFTs, are not possible, while platforms race to the bottom and remove royalty support.

Inscriptions avoid this situation entirely by making no false promises of supporting royalties on-chain, thus avoiding the confusion, chaos, and negativity of the Ethereum NFT situation.

Inscriptions unlock new markets.

Groestlcoin's market capitalization and liquidity are greater than Ethereum's by a large margin. Much of this liquidity is not available to Ethereum NFTs, since many Groestlcoiners prefer not to interact with the Ethereum ecosystem due to concerns related to simplicity, security, and decentralization.

Such Groestlcoiners may be more interested in inscriptions than Ethereum NFTs, unlocking new classes of collector.

Inscriptions have a richer data model.

Inscriptions consist of a content type, also known as a MIME type, and content, which is an arbitrary byte string. This is the same data model used by the web, and allows inscription content to evolve with the web, and come to support any kind of content supported by web browsers, without requiring changes to the underlying protocol.

Inscriptions for…


Inscriptions are on Groestlcoin. Groestlcoin is the digital currency with the highest status and greatest chance of long-term survival. If you want to guarantee that your art survives into the future, there is no better way to publish it than as inscriptions.

Cheaper on-chain storage. At $0,40 per GRS and the minimum relay fee of 1 gro per vbyte, publishing inscription content costs $0.0025 per 1 million bytes.

Inscriptions are early! Inscriptions are still in development, and have not yet launched on mainnet. This gives you an opportunity to be an early adopter, and explore the medium as it evolves.

Inscriptions are simple. Inscriptions do not require writing or understanding smart contracts.

Inscriptions unlock new liquidity. Inscriptions are more accessible and appealing to groestlcoin holders, unlocking an entirely new class of collector.

Inscriptions are designed for digital artifacts. Inscriptions are designed from the ground up to support NFTs, and feature a better data model, and features like globally unique symbols and enhanced provenance.

Inscriptions do not support on-chain royalties. This is negative, but only depending on how you look at it. On-chain royalties have been a boon for creators, but have also created a huge amount of confusion in the Ethereum NFT ecosystem. The ecosystem now grapples with this issue, and is engaged in a race to the bottom, towards a royalties-optional future. Inscriptions have no support for on-chain royalties, because they are technically infeasible. If you choose to create inscriptions, there are many ways you can work around this limitation: withhold a portion of your inscriptions for future sale, to benefit from future appreciation, or perhaps offer perks for users who respect optional royalties.


Inscriptions are simple, clear, and have no surprises. They are always immutable and on-chain, with no special due diligence required.

Inscriptions are on Groestlcoin. You can verify the location and properties of inscriptions easily with Groestlcoin full node that you control.


Let me begin this section by saying: the most important thing that the Groestlcoin network does is decentralize money. All other use-cases are secondary, including ordinal theory. The developers of ordinal theory understand and acknowledge this, and believe that ordinal theory helps, at least in a small way, Groestlcoin's primary mission.

Digital artifacts have merit. There are, of course, a great deal of NFTs that are ugly, stupid, and fraudulent. However, there are many that are fantastically creative, and creating and collecting art has been a part of the human story since its inception, and predates even trade and money, which are also ancient technologies.

Groestlcoin provides an amazing platform for creating and collecting digital artifacts in a secure, decentralized way, that protects users and artists in the same way that it provides an amazing platform for sending and receiving value, and for all the same reasons.

Ordinals and inscriptions increase demand for Groestlcoin block space, which increase Groestlcoin's security budget, which is vital for safeguarding Groestlcoin's transition to a fee-dependent security model, as the block subsidy is halved into insignificance.

Inscription content is stored on-chain, and thus the demand for block space for use in inscriptions is unlimited. This creates a buyer of last resort for all Groestlcoin block space. This will help support a robust fee market, which ensures that Groestlcoin remains secure.

Inscriptions also counter the narrative that Groestlcoin cannot be extended or used for new use-cases. Inscriptions provide a counter argument which is easy to understand, and which targets a popular and proven use case, NFTs, which makes it highly legible.

If inscriptions prove, as the authors hope, to be highly sought after digital artifacts with a rich history, they will serve as a powerful hook for Groestlcoin adoption: come for the fun, rich art, stay for the decentralized digital money.

Inscriptions are an extremely benign source of demand for block space. Unlike, for example, stablecoins, which potentially give large stablecoin issuers influence over the future of Groestlcoin development, or DeFi, which might centralize mining by introducing opportunities for MEV, digital art and collectables on Groestlcoin, are unlikely to produce individual entities with enough power to corrupt Groestlcoin. Art is decentralized.

Inscription users and service providers are incentivized to run Groestlcoin full nodes, to publish and track inscriptions, and thus throw their economic weight behind the honest chain.

Ordinal theory and inscriptions do not meaningfully affect Groestlcoin's fungibility. Groestlcoin users can ignore both and be unaffected.

We hope that ordinal theory strengthens and enriches groestlcoin, and gives it another dimension of appeal and functionality, enabling it more effectively serve its primary use case as humanity's decentralized store of value.

Contributing to ord

Suggested Steps

  1. Find an issue you want to work on.
  2. Figure out what would be a good first step towards resolving the issue. This could be in the form of code, research, a proposal, or suggesting that it be closed, if it's out of date or not a good idea in the first place.
  3. Comment on the issue with an outline of your suggested first step, and asking for feedback. Of course, you can dive in and start writing code or tests immediately, but this avoids potentially wasted effort, if the issue is out of date, not clearly specified, blocked on something else, or otherwise not ready to implement.
  4. If the issue requires a code change or bugfix, open a draft PR with tests, and ask for feedback. This makes sure that everyone is on the same page about what needs to be done, or what the first step in solving the issue should be. Also, since tests are required, writing the tests first makes it easy to confirm that the change can be tested easily.
  5. Mash the keyboard randomly until the tests pass, and refactor until the code is ready to submit.
  6. Mark the PR as ready to review.
  7. Revise the PR as needed.
  8. And finally, mergies!

Start small

Small changes will allow you to make an impact quickly, and if you take the wrong tack, you won't have wasted much time.

Ideas for small issues:

  • Add a new test or test case that increases test coverage
  • Add or improve documentation
  • Find an issue that needs more research, and do that research and summarize it in a comment
  • Find an out-of-date issue and comment that it can be closed
  • Find an issue that shouldn't be done, and provide constructive feedback detailing why you think that is the case

Merge early and often

Break up large tasks into multiple smaller steps that individually make progress. If there's a bug, you can open a PR that adds a failing ignored test. This can be merged, and the next step can be to fix the bug and unignore the test. Do research or testing, and report on your results. Break a feature into small sub-features, and implement them one at a time.

Figuring out how to break down a larger PR into smaller PRs where each can be merged is an art form well-worth practicing. The hard part is that each PR must itself be an improvement.

I strive to follow this advice myself, and am always better off when I do.

Small changes are fast to write, review, and merge, which is much more fun than laboring over a single giant PR that takes forever to write, review, and merge. Small changes don't take much time, so if you need to stop working on a small change, you won't have wasted much time as compared to a larger change that represents many hours of work. Getting a PR in quickly improves the project a little bit immediately, instead of having to wait a long time for larger improvement. Small changes are less likely to accumulate merge conflict. As the Athenians said: The fast commit what they will, the slow merge what they must.

Get help

If you're stuck for more than 15 minutes, ask for help, like a Rust Discord, Stack Exchange, or in a project issue or discussion.

Practice hypothesis-driven debugging

Formulate a hypothesis as to what is causing the problem. Figure out how to test that hypothesis. Perform that tests. If it works, great, you fixed the issue or now you know how to fix the issue. If not, repeat with a new hypothesis.

Pay attention to error messages

Read all error messages and don't tolerate warnings.


Ordinals is an open-source project by Groestlcoin in development since early 2023.

You can donate here:

Ordinal Theory Guides

See the table of contents for a list of guides, including a guide to the explorer, a guide for gro hunters, and a guide to inscriptions.

Ordinal Explorer

The ord binary includes a block explorer. We host a instance of the block explorer on mainnet at, and on signet at

Running The Explorer

The server can be run locally with:

ord server

To specify a port add the --http-port flag:

ord server --http-port 8080

To enable the JSON-API endpoints add the --enable-json-api or -j flag (see here for more info):

ord --enable-json-api server

To test how your inscriptions will look you can run:

ord preview <FILE1> <FILE2> ...

The search box accepts a variety of object representations.


Blocks can be searched by hash, for example, the genesis block:



Transactions can be searched by hash, for example, the block 1 coinbase transaction:



Transaction outputs can searched by outpoint, for example, the only output of the genesis block coinbase transaction:



Gros can be searched by integer, their position within the entire groestlcoin supply:


By decimal, their block and offset within that block:


By degree, their cycle, blocks since the last halving, blocks since the last difficulty adjustment, and offset within their block:


By name, their base 26 representation using the letters "a" through "z":


Or by percentile, the percentage of groestlcoin's supply that has been or will have been issued when they are mined:



You can run ord with the --enable-json-api flag to access endpoints that return JSON instead of HTML if you set the HTTP Accept: application/json header. The structure of theses objects closely follows what is shown in the HTML. These endpoints are:

  • /inscription/<INSCRIPTION_ID>
  • /inscriptions
  • /inscriptions/block/<BLOCK_HEIGHT>
  • /inscriptions/block/<BLOCK_HEIGHT>/<PAGE_INDEX>
  • /inscriptions/<FROM>
  • /inscriptions/<FROM>/<N>
  • /output/<OUTPOINT>
  • /output/<OUTPOINT>
  • /sat/<SAT>

To get a list of the latest 100 inscriptions you would do:

curl -s -H "Accept: application/json" ''

To see information about a UTXO, which includes inscriptions inside it, do:

curl -s -H "Accept: application/json" ''

Which returns:

  "value": 10000,
  "script_pubkey": "OP_PUSHNUM_1 OP_PUSHBYTES_32 156cc4878306157720607cdcb4b32afa4cc6853868458d7258b907112e5a434b",
  "address": "grs1pz4kvfpurqc2hwgrq0nwtfve2lfxvdpfcdpzc6ujchyr3ztj6gd9sfr6ayf",
  "transaction": "bc4c30829a9564c0d58e6287195622b53ced54a25711d1b86be7cd3a70ef61ed",
  "sat_ranges": null,
  "inscriptions": [

Ordinal Inscription Guide

Individual gros can be inscribed with arbitrary content, creating Groestlcoin-native digital artifacts that can be held in a Groestlcoin wallet and transferred using Groestlcoin transactions. Inscriptions are as durable, immutable, secure, and decentralized as Groestlcoin itself.

Working with inscriptions requires a Groestlcoin full node, to give you a view of the current state of the Groestlcoin blockchain, and a wallet that can create inscriptions and perform gro control when constructing transactions to send inscriptions to another wallet.

Groestlcoin Core provides both a Groestlcoin full node and wallet. However, the Groestlcoin Core wallet cannot create inscriptions and does not perform gro control.

This requires ord, the ordinal utility. ord doesn't implement its own wallet, so ord wallet subcommands interact with Groestlcoin Core wallets.

This guide covers:

  1. Installing Groestlcoin Core
  2. Syncing the Groestlcoin blockchain
  3. Creating a Groestlcoin Core wallet
  4. Using ord wallet receive to receive gros
  5. Creating inscriptions with ord wallet inscribe
  6. Sending inscriptions with ord wallet send
  7. Receiving inscriptions with ord wallet receive

Getting Help

If you get stuck, try asking for help on the Groestlcoin Discord Server, or checking GitHub for relevant issues.

Installing Groestlcoin Core

Groestlcoin Core is available from

Making inscriptions requires Groestlcoin Core 24 or newer.

This guide does not cover installing Groestlcoin Core in detail. Once Groestlcoin Core is installed, you should be able to run groestlcoind -version successfully from the command line. Do NOT use groestlcoin-qt.

Configuring Groestlcoin Core

ord requires Groestlcoin Core's transaction index and rest interface.

To configure your Groestlcoin Core node to maintain a transaction index, add the following to your groestlcoin.conf:


Or, run groestlcoind with -txindex:

groestlcoind -txindex

Details on creating or modifying your groestlcoin.conf file can be found here.

Syncing the Groestlcoin Blockchain

To sync the chain, run:

groestlcoind -txindex

…and leave it running until getblockcount:

groestlcoin-cli getblockcount

agrees with the block count on a block explorer like the block explorer. ord interacts with groestlcoind, so you should leave groestlcoind running in the background when you're using ord.

The blockchain takes about 600GB of disk space. If you have an external drive you want to store blocks on, use the configuration option blocksdir=<external_drive_path>. This is much simpler than using the datadir option because the cookie file will still be in the default location for groestlcoin-cli and ord to find.


Make sure you can access groestlcoind with groestlcoin-cli -getinfo and that it is fully synced.

If groestlcoin-cli -getinfo returns Could not connect to the server, groestlcoind is not running.

Make sure rpcuser, rpcpassword, or rpcauth are NOT set in your groestlcoin.conf file. ord requires using cookie authentication. Make sure there is a file .cookie in your groestlcoin data directory.

If groestlcoin-cli -getinfo returns Could not locate RPC credentials, then you must specify the cookie file location. If you are using a custom data directory (specifying the datadir option), then you must specify the cookie location like groestlcoin-cli -rpccookiefile=<your_groestlcoin_datadir>/.cookie -getinfo. When running ord you must specify the cookie file location with --cookie-file=<your_groestlcoin_datadir>/.cookie.

Make sure you do NOT have disablewallet=1 in your groestlcoin.conf file. If groestlcoin-cli listwallets returns Method not found then the wallet is disabled and you won't be able to use ord.

Make sure txindex=1 is set. Run groestlcoin-cli getindexinfo and it should return something like

  "txindex": {
    "synced": true,
    "best_block_height": 776546

If it only returns {}, txindex is not set. If it returns "synced": false, groestlcoind is still creating the txindex. Wait until "synced": true before using ord.

If you have maxuploadtarget set it can interfere with fetching blocks for ord index. Either remove it or set whitebind=

Installing ord

The ord utility is written in Rust and can be built from source. Pre-built binaries are available on the releases page.

You can install the latest pre-built binary from the command line with:

curl --proto '=https' --tlsv1.2 -fsLS | bash -s

Once ord is installed, you should be able to run:

ord --version

Which prints out ord's version number.

Creating a Groestlcoin Core Wallet

ord uses Groestlcoin Core to manage private keys, sign transactions, and broadcast transactions to the Groestlcoin network.

To create a Groestlcoin Core wallet named ord for use with ord, run:

ord wallet create

Receiving Gros

Inscriptions are made on individual gros, using normal Groestlcoin transactions that pay fees in gros, so your wallet will need some gros.

Get a new address from your ord wallet by running:

ord wallet receive

And send it some funds.

You can see pending transactions with:

ord wallet transactions

Once the transaction confirms, you should be able to see the transactions outputs with ord wallet outputs.

Creating Inscription Content

Gros can be inscribed with any kind of content, but the ord wallet only supports content types that can be displayed by the ord block explorer.

Additionally, inscriptions are included in transactions, so the larger the content, the higher the fee that the inscription transaction must pay.

Inscription content is included in transaction witnesses, which receive the witness discount. To calculate the approximate fee that an inscribe transaction will pay, divide the content size by four and multiply by the fee rate.

Inscription transactions must be less than 400,000 weight units, or they will not be relayed by Groestlcoin Core. One byte of inscription content costs one weight unit. Since an inscription transaction includes not just the inscription content, limit inscription content to less than 400,000 weight units. 390,000 weight units should be safe.

Creating Inscriptions

To create an inscription with the contents of FILE, run:

ord wallet inscribe --fee-rate FEE_RATE FILE

Ord will output two transactions IDs, one for the commit transaction, and one for the reveal transaction, and the inscription ID. Inscription IDs are of the form TXIDiN, where TXID is the transaction ID of the reveal transaction, and N is the index of the inscription in the reveal transaction.

The commit transaction commits to a tapscript containing the content of the inscription, and the reveal transaction spends from that tapscript, revealing the content on chain and inscribing it on the first gro of the input that contains the corresponding tapscript.

Wait for the reveal transaction to be mined. You can check the status of the commit and reveal transactions using the esplora block explorer.

Once the reveal transaction has been mined, the inscription ID should be printed when you run:

ord wallet inscriptions

Parent-Child Inscriptions

Parent-child inscriptions enable what is colloquially known as collections, see provenance for more information.

To make an inscription a child of another, the parent inscription has to be inscribed and present in the wallet. To choose a parent run ord wallet inscriptions and copy the inscription id (<PARENT_INSCRIPTION_ID>).

Now inscribe the child inscription and specify the parent like so:

ord wallet inscribe --fee-rate FEE_RATE --parent <PARENT_INSCRIPTION_ID> CHILD_FILE

This relationship cannot be added retroactively, the parent has to be present at inception of the child.

Sending Inscriptions

Ask the recipient to generate a new address by running:

ord wallet receive

Send the inscription by running:

ord wallet send --fee-rate <FEE_RATE> <ADDRESS> <INSCRIPTION_ID>

See the pending transaction with:

ord wallet transactions

Once the send transaction confirms, the recipient can confirm receipt by running:

ord wallet inscriptions

Receiving Inscriptions

Generate a new receive address using:

ord wallet receive

The sender can transfer the inscription to your address using:


See the pending transaction with:

ord wallet transactions

Once the send transaction confirms, you can can confirm receipt by running:

ord wallet inscriptions

Gro Hunting

This guide is out of date. Since it was written, the ord binary was changed to only build the full gro index when the --index-sats flag is supplied. Additionally, ord now has a built-in wallet that wraps a Groestlcoin Core wallet. See ord wallet --help.

Ordinal hunting is difficult but rewarding. The feeling of owning a wallet full of UTXOs, redolent with the scent of rare and exotic gros, is beyond compare.

Ordinals are numbers for gros. Every gro has an ordinal number and every ordinal number has a gro.


There are a few things you'll need before you start.

  1. First, you'll need a synced Groestlcoin Core node with a transaction index. To turn on transaction indexing, pass -txindex on the command-line:

    groestlcoind -txindex

    Or put the following in your Groestlcoin configuration file:


    Launch it and wait for it to catch up to the chain tip, at which point the following command should print out the current block height:

    groestlcoin-cli getblockcount
  2. Second, you'll need a synced ord index.

    • Get a copy of ord from the repo.

    • Run RUST_LOG=info ord index. It should connect to your groestlcoin core node and start indexing.

    • Wait for it to finish indexing.

  3. Third, you'll need a wallet with UTXOs that you want to search.

Searching for Rare Ordinals

Searching for Rare Ordinals in a Groestlcoin Core Wallet

The ord wallet command is just a wrapper around Groestlcoin Core's RPC API, so searching for rare ordinals in a Groestlcoin Core wallet is Easy. Assuming your wallet is named foo:

  1. Load your wallet:

    groestlcoin-cli loadwallet foo
  2. Display any rare ordinals wallet foo's UTXOs:

    ord wallet sats

Searching for Rare Ordinals in a Non-Groestlcoin Core Wallet

The ord wallet command is just a wrapper around Groestlcoin Core's RPC API, so to search for rare ordinals in a non-Groestlcoin Core wallet, you'll need to import your wallet's descriptors into Groestlcoin Core.

Descriptors describe the ways that wallets generate private keys and public keys.

You should only import descriptors into Groestlcoin Core for your wallet's public keys, not its private keys.

If your wallet's public key descriptor is compromised, an attacker will be able to see your wallet's addresses, but your funds will be safe.

If your wallet's private key descriptor is compromised, an attacker can drain your wallet of funds.

  1. Get the wallet descriptor from the wallet whose UTXOs you want to search for rare ordinals. It will look something like this:

  2. Create a watch-only wallet named foo-watch-only:

    groestlcoin-cli createwallet foo-watch-only true true

    Feel free to give it a better name than foo-watch-only!

  3. Load the foo-watch-only wallet:

    groestlcoin-cli loadwallet foo-watch-only
  4. Import your wallet descriptors into foo-watch-only:

    groestlcoin-cli importdescriptors \
      '[{ "desc": "wpkh([bf1dd55e/84h/0h/0h]xpub6CcJtWcvFQaMo39ANFi1MyXkEXM8T8ZhnxMtSjQAdPmVSTHYnc8Hwoc11VpuP8cb8JUTboZB5A7YYGDonYySij4XTawL6iNZvmZwdnSEEep/0/*)#tpnxnxax", "timestamp":0 }]'

    If you know the Unix timestamp when your wallet first started receive transactions, you may use it for the value of "timestamp" instead of 0. This will reduce the time it takes for Groestlcoin Core to search for your wallet's UTXOs.

  5. Check that everything worked:

    groestlcoin-cli getwalletinfo
  6. Display your wallet's rare ordinals:

    ord wallet sats

Searching for Rare Ordinals in a Wallet that Exports Multi-path Descriptors

Some descriptors describe multiple paths in one descriptor using angle brackets, e.g., <0;1>. Multi-path descriptors are not yet supported by Groestlcoin Core, so you'll first need to convert them into multiple descriptors, and then import those multiple descriptors into Groestlcoin Core.

  1. First get the multi-path descriptor from your wallet. It will look something like this:

  2. Create a descriptor for the receive address path:


    And the change address path:

  3. Get and note the checksum for the receive address descriptor, in this case tpnxnxax:

    groestlcoin-cli getdescriptorinfo \
      "descriptor": "wpkh([bf1dd55e/84'/0'/0']xpub6CcJtWcvFQaMo39ANFi1MyXkEXM8T8ZhnxMtSjQAdPmVSTHYnc8Hwoc11VpuP8cb8JUTboZB5A7YYGDonYySij4XTawL6iNZvmZwdnSEEep/0/*)#csvefu29",
      "checksum": "tpnxnxax",
      "isrange": true,
      "issolvable": true,
      "hasprivatekeys": false

    And for the change address descriptor, in this case 64k8wnd7:

    groestlcoin-cli getdescriptorinfo \
      "descriptor": "wpkh([bf1dd55e/84'/0'/0']xpub6CcJtWcvFQaMo39ANFi1MyXkEXM8T8ZhnxMtSjQAdPmVSTHYnc8Hwoc11VpuP8cb8JUTboZB5A7YYGDonYySij4XTawL6iNZvmZwdnSEEep/1/*)#fyfc5f6a",
      "checksum": "64k8wnd7",
      "isrange": true,
      "issolvable": true,
      "hasprivatekeys": false
  4. Load the wallet you want to import the descriptors into:

    groestlcoin-cli loadwallet foo-watch-only
  5. Now import the descriptors, with the correct checksums, into Groestlcoin Core.

    groestlcoin-cli \
     importdescriptors \
         "desc": "wpkh([bf1dd55e/84h/0h/0h]xpub6CcJtWcvFQaMo39ANFi1MyXkEXM8T8ZhnxMtSjQAdPmVSTHYnc8Hwoc11VpuP8cb8JUTboZB5A7YYGDonYySij4XTawL6iNZvmZwdnSEEep/0/*)#tpnxnxax"
         "desc": "wpkh([bf1dd55e/84h/0h/0h]xpub6CcJtWcvFQaMo39ANFi1MyXkEXM8T8ZhnxMtSjQAdPmVSTHYnc8Hwoc11VpuP8cb8JUTboZB5A7YYGDonYySij4XTawL6iNZvmZwdnSEEep/1/*)#64k8wnd7",

    If you know the Unix timestamp when your wallet first started receive transactions, you may use it for the value of the "timestamp" fields instead of 0. This will reduce the time it takes for Groestlcoin Core to search for your wallet's UTXOs.

  6. Check that everything worked:

    groestlcoin-cli getwalletinfo
  7. Display your wallet's rare ordinals:

    ord wallet sats

Exporting Descriptors

Sparrow Wallet

Navigate to the Settings tab, then to Script Policy, and press the edit button to display the descriptor.

Transferring Ordinals

The ord wallet supports transferring specific gros. You can also use groestlcoin-cli commands createrawtransaction, signrawtransactionwithwallet, and sendrawtransaction, how to do so is complex and outside the scope of this guide.


Currently, ord is the only wallet supporting gro-control and gro-selection, which are required to safely store and send rare gros and inscriptions, hereafter ordinals.

The recommended way to send, receive, and store ordinals is with ord, but if you are careful, it is possible to safely store, and in some cases send, ordinals with other wallets.

As a general note, receiving ordinals in an unsupported wallet is not dangerous. Ordinals can be sent to any groestlcoin address, and are safe as long as the UTXO that contains them is not spent. However, if that wallet is then used to send groestlcoin, it may select the UTXO containing the ordinal as an input, and send the inscription or spend it to fees.

A guide to creating an ord-compatible wallet with Sparrow-GRS Wallet, is available in this handbook.

Please note that if you follow this guide, you should not use the wallet you create to send GRS, unless you perform manual coin-selection to avoid sending ordinals.

Collecting Inscriptions and Ordinals with Sparrow Wallet

Users who cannot or have not yet set up the ord wallet can receive inscriptions and ordinals with alternative groestlcoin wallets, as long as they are very careful about how they spend from that wallet.

This guide gives some basic steps on how to create a wallet with Sparrow Wallet which is compatible with ord and can be later imported into ord

⚠️⚠️ Warning!! ⚠️⚠️

As a general rule if you take this approach, you should use this wallet with the Sparrow software as a receive-only wallet.

Do not spend any gros from this wallet unless you are sure you know what you are doing. You could very easily inadvertently lose access to your ordinals and inscriptions if you don't heed this warning.

Wallet Setup & Receiving

Download the Sparrow Wallet from the releases page for your particular operating system.

Select File -> New Wallet and create a new wallet called ord.

Change the Script Type to Taproot (P2TR) and select the New or Imported Software Wallet option.

Select Use 12 Words and then click Generate New. Leave the passphrase blank.

A new 12 word BIP39 seed phrase will be generated for you. Write this down somewhere safe as this is your backup to get access to your wallet. NEVER share or show this seed phrase to anyone else.

Once you have written down the seed phrase click Confirm Backup.

Re-enter the seed phrase which you wrote down, and then click Create Keystore.

Click Import Keystore.

Click Apply. Add a password for the wallet if you want to.

You now have a wallet which is compatible with ord, and can be imported into ord using the BIP39 Seed Phrase. To receive ordinals or inscriptions, click on the Receive tab and copy a new address.

Each time you want to receive you should use a brand-new address, and not re-use existing addresses.

Note that groestlcoin is different to some other blockchain wallets, in that this wallet can generate an unlimited number of new addresses. You can generate a new address by clicking on the Get Next Address button. You can see all of your addresses in the Addresses tab of the app.

You can add a label to each address, so you can keep track of what it was used for.

Validating / Viewing Received Inscriptions

Once you have received an inscription you will see a new transaction in the Transactions tab of Sparrow, as well as a new UTXO in the UTXOs tab.

Initially this transaction may have an "Unconfirmed" status, and you will need to wait for it to be mined into a groestlcoin block before it is fully received.

To track the status of your transaction you can right-click on it, select Copy Transaction ID and then paste that transaction id into

Once the transaction has confirmed, you can validate and view your inscription by heading over to the UTXOs tab, finding the UTXO you want to check, right-clicking on the Output and selecting Copy Transaction Output. This transaction output id can then be pasted into the search.

Freezing UTXO's

As explained above, each of your inscriptions is stored in an Unspent Transaction Output (UTXO). You want to be very careful not to accidentally spend your inscriptions, and one way to make it harder for this to happen is to freeze the UTXO.

To do this, go to the UTXOs tab, find the UTXO you want to freeze, right-click on the Output and select Freeze UTXO.

This UTXO (Inscription) is now un-spendable within the Sparrow Wallet until you unfreeze it.

Importing into ord wallet

For details on setting up Groestlcoin Core and the ord wallet check out the Inscriptions Guide

When setting up ord, instead of running ord wallet create to create a brand-new wallet, you can import your existing wallet using ord wallet restore "BIP39 SEED PHRASE" using the seed phrase you generated with Sparrow Wallet.

There is currently a bug which causes an imported wallet to not be automatically rescanned against the blockchain. To work around this you will need to manually trigger a rescan using the groestlcoin core cli: groestlcoin-cli -rpcwallet=ord rescanblockchain 767430

You can then check your wallet's inscriptions using ord wallet inscriptions

Note that if you have previously created a wallet with ord, then you will already have a wallet with the default name, and will need to give your imported wallet a different name. You can use the --wallet parameter in all ord commands to reference a different wallet, eg:

ord --wallet ord_from_sparrow wallet restore "BIP39 SEED PHRASE"

ord --wallet ord_from_sparrow wallet inscriptions

groestlcoin-cli -rpcwallet=ord_from_sparrow rescanblockchain 767430

Sending inscriptions with Sparrow Wallet

⚠️⚠️ Warning ⚠️⚠️

While it is highly recommended that you set up a groestlcoin core node and run the ord software, there are certain limited ways you can send inscriptions out of Sparrow Wallet in a safe way. Please note that this is not recommended, and you should only do this if you fully understand what you are doing.

Using the ord software will remove much of the complexity we are describing here, as it is able to automatically and safely handle sending inscriptions in an easy way.

⚠️⚠️ Additional Warning ⚠️⚠️

Don't use your sparrow inscriptions wallet to do general sends of non-inscription groestlcoin. You can setup a separate wallet in sparrow if you need to do normal groestlcoin transactions, and keep your inscriptions wallet separate.

Groestlcoin's UTXO model

Before sending any transaction it's important that you have a good mental model for groestlcoin's Unspent Transaction Output (UTXO) system. The way Groestlcoin works is fundamentally different to many other blockchains such as Ethereum. In Ethereum generally you have a single address in which you store ETH, and you cannot differentiate between any of the ETH - it is just all a single value of the total amount in that address. Groestlcoin works very differently in that we generate a new address in the wallet for each receive, and every time you receive gros to an address in your wallet you are creating a new UTXO. Each UTXO can be seen and managed individually. You can select specific UTXO's which you want to spend, and you can choose not to spend certain UTXO's.

Some Groestlcoin wallets do not expose this level of detail, and they just show you a single summed up value of all the groestlcoin in your wallet. However, when sending inscriptions it is important that you use a wallet like Sparrow which allows for UTXO control.

Inspecting your inscription before sending

Like we have previously described inscriptions are inscribed onto gros, and gros are stored within UTXOs. UTXO's are a collection of gros with some particular value of the number of gros (the output value). Usually (but not always) the inscription will be inscribed on the first gro in the UTXO.

When inspecting your inscription before sending the main thing you will want to check is which gro in the UTXO your inscription is inscribed on.

To do this, you can follow the Validating / Viewing Received Inscriptions described above to find the inscription page for your inscription on

There you will find some metadata about your inscription which looks like the following:

There is a few of important things to check here:

  • The output identifier matches the identifier of the UTXO you are going to send
  • The offset of the inscription is 0 (this means that the inscription is located on the first gro in the UTXO)
  • the output_value has enough gros to cover the transaction fee (postage) for sending the transaction. The exact amount you will need depends on the fee rate you will select for the transaction

If all of the above are true for your inscription, it should be safe for you to send it using the method below.

⚠️⚠️ Be very careful sending your inscription particularly if the offset value is not 0. It is not recommended to use this method if that is the case, as doing so you could accidentally send your inscription to a groestlcoin miner unless you know what you are doing.

Sending your inscription

To send an inscription navigate to the UTXOs tab, and find the UTXO which you previously validated contains your inscription.

If you previously froze the UXTO you will need to right-click on it and unfreeze it.

Select the UTXO you want to send, and ensure that is the only UTXO is selected. You should see UTXOs 1/1 in the interface. Once you are sure this is the case you can hit Send Selected.

You will then be presented with the transaction construction interface. There is a few things you need to check here to make sure that this is a safe send:

  • The transaction should have only 1 input, and this should be the UTXO with the label you want to send
  • The transaction should have only 1 output, which is the address/label where you want to send the inscription

If your transaction looks any different, for example you have multiple inputs, or multiple outputs then this may not be a safe transfer of your inscription, and you should abandon sending until you understand more, or can import into the ord wallet.

You should set an appropriate transaction fee, Sparrow will usually recommend a reasonable one, but you can also check to see what the recommended fee rate is for sending a transaction.

You should add a label for the recipient address, a label like alice address for inscription #123 would be ideal.

Once you have checked the transaction is a safe transaction using the checks above, and you are confident to send it you can click Create Transaction.

Here again you can double check that your transaction looks safe, and once you are confident you can click Finalize Transaction for Signing.

Here you can triple check everything before hitting Sign.

And then actually you get very very last chance to check everything before hitting Broadcast Transaction. Once you broadcast the transaction it is sent to the groestlcoin network, and starts being propagated into the mempool.

If you want to track the status of your transaction you can copy the Transaction Id (Txid) and paste that into

Once the transaction has confirmed you can check the inscription page on to validate that it has moved to the new output location and address.


Sparrow wallet is not showing a transaction/UTXO, but I can see it on!

Make sure that your wallet is connected to a groestlcoin node. To validate this, head into the Preferences-> Server settings, and click Edit Existing Connection.

From there you can select a node and click Test Connection to validate that Sparrow is able to connect successfully.


Ord can be tested using the following flags to specify the test network.

Most ord commands in inscriptions and explorer can be run with the following network flags:

Testnet--testnet or -t
Signet--signet or -s
Regtest--regtest or -r

Regtest doesn't require downloading the blockchain or indexing ord.


Run groestlcoind in regtest with:

groestlcoind -regtest -txindex

Create a wallet in regtest with:

ord -r wallet create

Get a regtest receive address with:

ord -r wallet receive

Mine 101 blocks (to unlock the coinbase) with:

groestlcoin-cli -regtest generatetoaddress 101 <receive address>

Inscribe in regtest with:

ord -r wallet inscribe --fee-rate 1 <file>

Mine the inscription with:

groestlcoin-cli -regtest generatetoaddress 1 <receive address>

View the inscription in the regtest explorer:

ord -r server

Testing Recursion

When testing out recursion, inscribe the dependencies first (example with p5.js):

ord -r wallet inscribe --fee-rate 1 p5.js

This should return a inscription_id which you can then reference in your recursive inscription.

ATTENTION: These ids will be different when inscribing on mainnet or signet, so be sure to change those in your recursive inscription for each chain.

Then you can inscribe your recursive inscription with:

ord -r wallet inscribe --fee-rate 1 recursive-inscription.html

Finally you will have to mine some blocks and start the server:

groestlcoin-cli generatetoaddress 6 <receive address>
ord -r server


ord includes a block explorer, which you can run locally with ord server.

The block explorer allows viewing inscriptions. Inscriptions are user-generated content, which may be objectionable or unlawful.

It is the responsibility of each individual who runs an ordinal block explorer instance to understand their responsibilities with respect to unlawful content, and decide what moderation policy is appropriate for their instance.

In order to prevent particular inscriptions from being displayed on an ord instance, they can be included in a YAML config file, which is loaded with the --config option.

To hide inscriptions, first create a config file, with the inscription ID you want to hide:

- 0000000000000000000000000000000000000000000000000000000000000000i0

The suggested name for ord config files is ord.yaml, but any filename can be used.

Then pass the file to --config when starting the server:

ord --config ord.yaml server

Note that the --config option comes after ord but before the server subcommand.

ord must be restarted in to load changes to the config file.

The instances use systemd to run the ord server service, which is called ord, with a config file located at /var/lib/ord/ord.yaml.

To hide an inscription on

  1. SSH into the server
  2. Add the inscription ID to /var/lib/ord/ord.yaml
  3. Restart the service with systemctl restart ord
  4. Monitor the restart with journalctl -u ord

Currently, ord is slow to restart, so the site will not come back online immediately.


Sometimes the ord database must be reindexed, which means deleting the database and restarting the indexing process with either ord index update or ord server. Reasons to reindex are:

  1. A new major release of ord, which changes the database scheme
  2. The database got corrupted somehow

The database ord uses is called redb, so we give the index the default file name index.redb. By default we store this file in different locations depending on your operating system.

Linux$XDG_DATA_HOME/ord or $HOME/.local/share/ord/home/alice/.local/share/ord
macOS$HOME/Library/Application Support/ord/Users/Alice/Library/Application Support/ord

So to delete the database and reindex on MacOS you would have to run the following commands in the terminal:

rm ~/Library/Application Support/ord/index.redb
ord index update

You can of course also set the location of the data directory yourself with ord --data-dir <DIR> index update or give it a specific filename and path with ord --index <FILENAME> index update.

Ordinal Bounty Hunting Hints

  • The ord wallet can send and receive specific gros. Additionally, ordinal theory is extremely simple. A clever hacker should be able to write code from scratch to manipulate gros using ordinal theory in no time.

  • For more information about ordinal theory, check out the FAQ for an overview, the BIP for the technical details, and the ord repo for the ord wallet and block explorer.

  • Satoshi was the original developer of ordinal theory. However, he knew that others would consider it heretical and dangerous, so he hid his knowledge, and it was lost to the sands of time. This potent theory is only now being rediscovered. You can help by researching rare gros.

Good luck and godspeed!

Ordinal Bounty 0


Send a gro whose ordinal number ends with a zero to the submission address:

✅: 1857578125803250

❌: 1857578125803251

The gro must be the first gro of the output you send.


100,000 gros

Submission Address

No longer accepting submissions.



Ordinal Bounty 1


The transaction that submits a UTXO containing the oldest gro, i.e., that with the lowest number, amongst all submitted UTXOs will be judged the winner.


200,000 gros

Submission Address

No longer accepting submissions.



Ordinal Bounty 2


Send an uncommon gro to the submission address:

✅: 347100000000000

❌: 6685000001337

Confirm that the submission address has not received transactions before submitting your entry. Only the first successful submission will be rewarded.


300,000 gros

Submission Address

No longer accepting submissions.



Ordinal Bounty 3


Ordinal bounty 3 has two parts, both of which are based on ordinal names. Ordinal names are a modified base-26 encoding of ordinal numbers. To avoid locking short names inside the unspendable genesis block coinbase reward, ordinal names get shorter as the ordinal number gets longer. The name of gro 0, the first gro to be mined is nvtdijuwxlp and the name of gro 2,099,999,997,689,999, the last gro to be mined, is a.

Both parts use frequency.tsv, a list of words and the number of times they occur in the Google Books Ngram dataset. filtered to only include the names of gros which will have been mined by the end of the submission period, that appear at least 5000 times in the corpus.

frequency.tsv is a file of tab-separated values. The first column is the word, and the second is the number of times it appears in the corpus. The entries are sorted from least-frequently occurring to most-frequently occurring.

frequency.tsv was compiled using this program.

To search an ord wallet for gros with a name in frequency.tsv, use the following ord command:

ord wallet sats --tsv frequency.tsv

This command requires the gro index, so --index-sats must be passed to ord when first creating the index.

Part 0

Rare gros pair best with rare words.

The transaction that submits the UTXO containing the gro whose name appears with the lowest number of occurrences in frequency.tsv shall be the winner of part 0.

Part 1

Popularity is the font of value.

The transaction that submits the UTXO containing the gro whose name appears with the highest number of occurrences in frequency.tsv shall be the winner of part 1.

Tie Breaking

In the case of a tie, where two submissions occur with the same frequency, the earlier submission shall be the winner.


  • Part 0: 200,000 gros
  • Part 1: 200,000 gros
  • Total: 400,000 gros

Submission Address

No longer accepting submissions.