What is a minor unit in ISO 4217?

The minor unit is the number of decimal digits a currency normally uses. USD has 2 (cents), JPY has 0 (no fractional yen), and BHD has 3 (fils). It tells you how to format and store amounts.

Why do some currencies have 0 decimal places?

Currencies like JPY, KRW, VND and UGX have no commonly used fractional subdivision, so ISO 4217 sets their minor unit to 0. When storing these in integer minor units, one major unit equals one minor unit.

How do I store money safely using these codes?

Store amounts as integers in the smallest minor unit (cents, fils) and keep the currency code alongside, then divide by 10^minor only for display. This avoids floating-point rounding errors entirely.

What is the numeric currency code for?

The three-digit numeric code mirrors the country's ISO 3166-1 numeric code where possible and is script-independent, which makes it useful in financial messaging formats and systems that avoid Latin letters.

Are codes like XAU and XDR real currencies?

They are ISO 4217 codes but not national currencies. XAU is one troy ounce of gold, XDR is the IMF Special Drawing Right. Codes starting with X are reserved for supranational, metal or testing uses.

What is the ISO 4217 Currency Codes?

Searchable ISO 4217 currency reference: three-letter alphabetic code, three-digit numeric code, number of minor-unit (decimal) digits and country for each currency, including zero-decimal currencies like JPY and KRW. It runs free in your browser on Gera Tools, with nothing uploaded.

ISO 4217 Currency Codes

Name: ISO 4217 Currency Codes
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

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ISO 4217 currency code reference

ISO 4217 standardizes the codes used to identify currencies in pricing, accounting and payment systems. Each currency has a three-letter alphabetic code (USD, EUR), a three-digit numeric code (840, 978), and a defined minor unit — the number of decimal places it normally uses. This reference is searchable by code, name or country and highlights the often-missed minor-unit count.

How it works

The alphabetic code is constructed from the country’s ISO 3166-1 alpha-2 code plus a letter for the currency: GB + P = GBP (Pound), US + D = USD (Dollar). Supranational and special codes start with X (EUR is an exception that predates the rule; XAU is gold, XDR is the IMF Special Drawing Right).

The crucial field for software is the minor unit (exponent):

amount_major = amount_minor / 10^minor

USD, minor 2:  150 cents  -> 1.50
JPY, minor 0:  150 yen    -> 150
BHD, minor 3:  150 fils   -> 0.150

Always store money as an integer count of minor units together with the currency code, then scale only when displaying. This prevents floating-point drift and makes the minor-unit table the single source of truth for formatting.

Currencies with non-standard minor units

Most currencies use two decimal places, but a significant number do not. Getting this wrong causes payment API errors, accounting mismatches, and overcharges:

Zero-decimal currencies (minor unit = 0)

Code	Currency	Country
JPY	Japanese yen	Japan
KRW	South Korean won	South Korea
VND	Vietnamese dong	Vietnam
UGX	Ugandan shilling	Uganda
IDR	Indonesian rupiah	Indonesia
PYG	Paraguayan guaraní	Paraguay
RWF	Rwandan franc	Rwanda

For these, the “amount in minor units” is the same as the face value. ¥2000 is sent to a payment API as 2000, not 200000.

Three-decimal currencies (minor unit = 3)

Code	Currency	Country
BHD	Bahraini dinar	Bahrain
KWD	Kuwaiti dinar	Kuwait
JOD	Jordanian dinar	Jordan
OMR	Omani rial	Oman
TND	Tunisian dinar	Tunisia

For these, 1.000 BHD is 1000 in minor units, and 1.5 BHD is 1500.

Tips and notes

Never assume two decimals. Hardcoding * 100 correctly handles USD, EUR, GBP, and most currencies — but silently corrupts JPY, KRW, BHD, KWD, and others. Always look up the exponent.
The numeric code is useful in systems that cannot carry Latin letters (financial messaging formats, legacy EDI systems) and usually mirrors the country’s ISO 3166-1 numeric code.
Codes beginning with X are not ordinary national currencies — they are supranational (EUR is an exception), commodity (XAU = gold, XAG = silver), or testing codes. Filter them out if you only want spendable money.
Pair every monetary amount with its currency code in storage. An integer amount without a currency code is meaningless — you cannot know if 1000 means ten dollars, one thousand yen, or one dinar.