Currency Formats

The XRP Ledger has two kinds of digital asset: XRP and tokens. Both types have high precision, although their formats are different.

Comparison

The following table summarizes some of the differences between XRP and tokens in the XRP Ledger:

For more information, see What is XRP? and Tokens.

Specifying Currency Amounts

Use the appropriate format for the type of currency you want to specify:

• XRP Amounts
• Token Amounts

XRP Amounts

To specify an amount of XRP, use a String Number indicating drops of XRP, where each drop is equal to 0.000001 XRP. For example, to specify 13.1 XRP:

"13100000"

Do not specify XRP as an object.

XRP amounts cannot be negative.

Token Amounts

To specify an amount of a (fungible) token, use an Amount object. This is a JSON object with three fields:

For example, to represent $153.75 US dollars issued by account r9cZA1mLK5R5Am25ArfXFmqgNwjZgnfk59, you would specify:

{
    "currency": "USD",
    "value": "153.75",
    "issuer": "r9cZA1mLK5R5Am25ArfXFmqgNwjZgnfk59"
}

Specifying Without Amounts

In some cases, you need to define an asset (which could be XRP or a token) without a specific amount, such as when defining an order book in the decentralized exchange.

To describe a token without an amount, specify it as a currency object, but omit the value field. For example:

{
  "currency": "TST",
  "issuer": "rP9jPyP5kyvFRb6ZiRghAGw5u8SGAmU4bd"
}

To describe XRP without an amount, specify it as a JSON object with only a currency field. Never include an issuer field for XRP. For example:

{
  "currency": "XRP"
}

String Numbers

XRP Ledger APIs generally use strings, rather than native JSON numbers, to represent numeric amounts of currency for both XRP and tokens. This protects against a loss of precision when using JSON parsers, which may automatically try to represent all JSON numbers in a floating-point format. Within the String value, the numbers are serialized in the same way as native JSON numbers:

• Base-10.
• Non-zero-prefaced.
• May contain . as a decimal point. For example, ½ is represented as 0.5. (American style, not European)
• Negative amounts start with the character -.
• May contain E or e to indicate being raised to a power of 10 (scientific notation). For example, 1.2E5 is equivalent to 1.2×10⁵, or 120000. Negative exponents are also possible.
• No comma (,) characters are used.

XRP Precision

XRP has the same precision as a 64-bit unsigned integer where each unit is equivalent to 0.000001 XRP. It uses integer math, so that any amount less than a full drop is rounded down.

Token Precision

Tokens can represent a wide variety of assets, including those typically measured in very small or very large denominations. This format uses significant digits and a power-of-ten exponent in a similar way to scientific notation. The format supports positive and negative significant digits and exponents within the specified range. Unlike typical floating-point representations of non-whole numbers, this format uses integer math for all calculations, so it always maintains 15 decimal digits of precision. Multiplication and division have adjustments to compensate for over-rounding in the least significant digits.

When sending token amounts in the XRP Ledger's peer-to-peer network, servers serialize the amount to a 64-bit binary value.

Currency Codes

The HTTP / WebSocket APIs support two formats of currency code:

• Standard Currency Codes: As a 3-character string such as "EUR" or "USD".
• Nonstandard Currency Codes: As a 160-bit hexadecimal string, such as "0158415500000000C1F76FF6ECB0BAC600000000". This is uncommon.

Tokens with the same code can ripple across connected trust lines. Currency codes have no other behavior built into the XRP Ledger.

Standard Currency Codes

The standard format for currency codes is a three-character string such as USD. This is intended for use with ISO 4217 Currency Codes. The following rules apply:

• Currency codes must be exactly 3 ASCII characters in length. The following characters are permitted: all uppercase and lowercase letters, digits, as well as the symbols ?, !, @, #, $, %, ^, &, *, <, >, (, ), {, }, [, ], and |.
• Currency codes are case-sensitive.
• The currency code XRP (all-uppercase) is disallowed. Real XRP typically does not use a currency code in the XRP Ledger protocol.

At the protocol level, this format is serialized into a 160-bit binary value starting with 0x00.

Nonstandard Currency Codes

You can also use a 160-bit (40-character) hexadecimal string such as 015841551A748AD2C1F76FF6ECB0CCCD00000000 as the currency code. To prevent this from being treated as a "standard" currency code, the first 8 bits MUST NOT be 0x00.

Deprecated: Some previous versions of ripple-lib supported an "interest-bearing" or "demurraging" currency code type. These codes have the first 8 bits 0x01. Demurraging / interest-bearing currencies are no longer supported, but you may find them in ledger data. For more information, see Demurrage.