description: Fungible Token colored coin standard backed by Satoshis

ARC20 Tokens

The Atomicals Protocol solves the long standing problem of how to represent arbitrary fungible token assets on the Bitcoin blockchain. The ARC-20 fungible token standard finally brings colored coins to Bitcoin and uses each Satoshi to represent ownership units of deployed tokens. This means that every unit of the token is backed by 1 Satoshi forever. It acts as a kind of "digital gold content" that underpins the value of the token. It also means every token can never go below 1 Satoshi in value, by definition.

ARC-20 uses the native Satoshi unit to represent each token, and they can be split and combined just like regular Bitcoins. ARC-20 tokens can be minted by anyone, and transferred to any Bitcoin address type, and works with wallets that support UTXO selection such as Sparrow Wallet (external link). There are two modes of deployment: direct and decentralized. Learn more below about the different ways the ARC-20 can be minted and their benefits.

The ARC-20 also comes with a built in ticker symbol service to provide a global unique name system for ticker symbols. The first registration of the ticker name is permanent and can never be used again.

Decentralized Mint

A decentralized is initialized with a ticker, per mint award, total mints allowed, start block height, and metadata. A deployer could initialize a ticker such as $myticker123 with a mint award of 1,000 units, with a total of 10,000 mints allowed and starting at block height 810,000 with an image.jpg and even meta data such as description, links, and terms.

Initialize (init-dft)

The basic format of the decentralized initialization using the Atomicals CLI is given as:

yarn cli init-dft <tick> <per_mint_amt> <mint_count> 
<start_height> metadata.json

Optional flags:
--mintbitworkc=<prefix>
--satsbyte=<number>

See format of metadata.json below

The decentralized initialize function init-dft allows minting for ticker tick to proceed with the mint-dft command (described below) only from the starting block height start_height and allowing a maximum of mint_count total mint requests, each to award per_mint_amt token units to the requester. The effective total max supply is per_mint_amt * mint_count.

Note: It will take 3 block confirmations before the tick ticker will be claimed. You can query the status with yarn cli get <atomicalID> or yarn cli find-tickers

Required Parameters:

tick: The globally unique ticker name

per_mint_amt: Number of units of the token to award per successful mint. Satoshi amount.

mint_count: Total number of permitted mints before exhausting the quota and becoming "fully minted"

start_height: Starting block height that mints may be begin. Can set block height to 0 or any future block height.

image: An image icon to represent the token. The name of the file will appear in the token. Use caution and rename the file first completely and include it as "image.jpg" or "image.png"

Optional Flags:

--mintbitworkc=<prefix>

Define an optional Bitwork mining prefix target for the mints. If set, then the minters must expend CPU energy to find a match for the prefix target to be allowed to mint successfully. This forces minters to perform proof of working mining in a similar manner to Bitcoin mining itself.

It is recommended to choose a prefix between 4 and 6 hex digits. You can use any valid hex digits between a-f0-9. It is intended to purely be a vanity transaction id and any value is sufficient to require minters to expend energy to mint the token.

Example time estimates for time required for minters:

Note: it could be any digit in the range a-f0-9, we use all 7's for illustration purpose only.

• 3 hex digit prefix of "777" will take about 4 seconds to mine
• 4 hex digit prefix of "7777" will take ~1 minute to mine
• 5 hex digit prefix of "77777" will take ~16 minutes to mine
• 6 hex digit prefix of "777777" will take ~256 minutes to mine

--satsbyte=<number>

Set the satoshis per byte for the transaction and override the default.

Initialize a Perpetual Minting token

yarn cli init-dft-perpetual <ticker>

Important Optional Parameters:

• max_mints: The number of mints allowed per mint phase. (Defaults to 2000)
• maxglobalmints: The number of global max mints.
• mint_amount: The number of tokens per mint. (Defaults to 10000)
• mint_height: The starting mint height.
• mintbitworkvec: The base vector of the bitwork prefix.
• mintbitworkcinc: The amount of bitworkc to increase for each phase of max_mints. (Defaults to 1)
• mintbitworkrinc: The amount of bitworkr to increase for each phase of max_mints.
• mintbitworkcincstart: The starting amount of bitworkc to increase for each phase of max_mints.
• mintbitworkrincstart: The starting amount of bitworkr to increase for each phase of max_mints.

See the complete arguments list using the command yarn cli init-dft-perpetual -h.

Below is an example of how to initialize a token with the same configuration of $infinity.

yarn cli init-dft-perpetual infinity2 \
  --max_mints=3333 \
  --mint_amount=9999 \
  --mintbitworkvec="888888888888888888888888" \
  --mintbitworkcinc=1

In mathematical terms, the relationship between the arguments in the function can be expressed as follows:

1. Target Calculation:

   • ( T_{\text{steps}} = \lfloor \frac{\text{actual_mints}}{\text{max_mints}} \rfloor )
   • ( T_{\text{current}} = \text{starting_target} + (T_{\text{steps}} \cdot \text{target_increment}) )

   The current target, ( T_{\text{current}} ), is computed based on the number of minted tokens relative to the maximum allowable mints, scaled by the target increment.

2. Bitwork Prefix Derivation:

   • ( \text{multiples} = \frac{T_{\text{current}}}{16} )
   • ( F_{\text{amount}} = \lfloor \text{multiples} \rfloor )
   • ( \text{modulo} = T_{\text{current}} \mod 16 )

   The resulting bitwork prefix string is derived from the base vector ( \text{bitwork_vec} ), padded to 32 characters, with:

   • The first ( F_{\text{amount}} ) characters forming the primary prefix.
   • If ( \text{modulo} > 0 ), it appends (".\text{modulo}") to the prefix.

Mint (mint-dft)

The basic format of the decentralized mint using the Atomicals CLI is given as:

yarn cli mint-dft <tick>

Optional flags:
--satsbyte=<number>

The decentralized mint function mint-dft allows minting for ticker tick to proceed starting from block height start_height.

Follow the on-screen instructions to mint.

Required Parameters:

tick: The globally unique ticker name

Optional Flags:

--satsbyte=<number>

Set the satoshis per byte for the transaction and override the default.

Direct Mint

The second way to mint or create an ARC-20 token type is to directly create a single output which contains the total supply, with each Satoshi representing a single unit of the token.

Mint entire supply in one step

yarn cli mint-ft <tick> <total_supply> metadata.json

Optional flags:
--satsbyte=<number>

See format of metadata.json below

The second way to mint or create an ARC-20 token type is to directly create a single output which contains the total supply, with each Satoshi representing a single unit of the token.

For example, to mint a token with a supply of 100,000,000, simply create a single output with exactly 1 full Bitcoin (since 1 BTC = 100,000,000 Satoshis). An advantage of using the direct minting mode is that the team who creates it must put up the required amount of Bitcoins to substantiate the total minted supply; which greatly reduces dishonest actors from printing tokens out of thin air.

Direct minting of ARC-20 is ideal for when a team or company wishes to maintain control over the initial distribution and determine how to spend the tokens at a later point in time.

Note: It will take 3 block confirmations before the tick ticker will be claimed. You can query the status with yarn cli get <atomicalID> or yarn cli find-tickers

Required Parameters:

tick: The globally unique ticker name

total_supply: Total supply units to directly mint

image: An image icon to represent the token. The name of the file will appear in the token. Use caution and rename the file first completely and include it as "image.jpg" or "image.png"

Optional Flags:

--satsbyte=<number>

Set the satoshis per byte for the transaction and override the default.

Metadata.json Format

Define metadata details into the token. The suggested format to use follows the convention sample-ft-meta.json.

Use Permanent File Storage to store an image on-chain and reference it in the "image" field below.

```json
{
    "name": "",
    "desc": "",
    "image": "atom:btc:dat:<location of store-file data>/image.png",
    "decimals": 0,
    "links": {
        "x": {
            "v": "https://x.com/..."
        },
        "website": {
            "v": "https://..."
        },
        "realm": {
            "v": "atom:btc:realm:myrealmname.subrealm"
        },
        "discord": {
            "v": "https://discord.gg/..."
        }
    },
    "legal": {
        "terms": ""
    }
}
```

None of the fields in the metadata are required, and can take any shape and form as long as it is valid JSON object. However it is recommended at a minimum name, description, and legal are provided to inform users of usage details. You must consult legal advice and verify your applicable jurisdictions permit your intended usage.