XAU — Gold (troy ounce)
metalHow to implement XAU safely
Gold uses ISO 4217 alpha code XAU and numeric code 959.
XAU appears in the current ISO 4217 list published 2026-01-01. ISO 4217 does not assign XAU a minor unit. The 4-digit precision used in examples is a display choice, not an ISO storage scale. Configure Intl.NumberFormat with currency: "XAU"; do not hardcode the symbol or assume every currency uses two decimals.
XAU is the reference symbol in this dataset. Store XAU alongside the amount so exports, payments, and accounting data remain unambiguous. Format for display only after choosing the user's locale, because symbol placement and separators belong to the locale rather than the currency record.
XAU represents a precious-metal unit rather than a national cash currency, so it has no country assignment in this directory. The record was checked against the SIX ISO 4217 source on 2026-07-19; recheck status-sensitive records when the Maintenance Agency publishes a new list.
- Status: active
- Numeric code: 959
- ISO minor unit: not applicable
- Verified: 2026-07-19
Reviewed 19 July 2026. Sources: SIX ISO 4217 current list
Formatting Examples
| Value | en-US |
|---|---|
| 1 | XAU 1.00 |
| 9.99 | XAU 9.99 |
| 100 | XAU 100.00 |
| 1234.56 | XAU 1,234.56 |
| 1000000 | XAU 1,000,000.00 |
Intl.NumberFormat
// Basic XAU formatting
new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'XAU',
}).format(1234.56);
// → "XAU 1,234.56"
// Minimum/maximum fraction digits
new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'XAU',
minimumFractionDigits: 4,
maximumFractionDigits: 4,
}).format(99);
// Example display precision: 4 decimal places
// ISO 4217 minor unit: not applicable
// ISO 4217 defines no integer storage scale for XAU.
// Choose and document product-specific precision.Continue your localization implementation
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