isValidIanaTimezoneId()

Alpha API. Initial API, highly likely to change outside SemVer. Don’t build on it in production. See API maturity.

Tests whether timezoneId is a valid IANA timezone identifier according to the runtime ICU data (via Intl.DateTimeFormat). The BROWSER_DETECTED sentinel is not a valid IANA ID — use isValidDashboardTimezoneId() for values stored on the dashboard.

Identifiers are case-sensitive. Intl accepts timezones case-insensitively, so a value that only differs in case from the canonical form (e.g. "america/new_york") is rejected. Aliases that resolve to a different identifier (e.g. "Etc/UTC" → "UTC") are still accepted as ICU-known IDs. Offset-style identifiers (e.g. "+01", "+0100", "+01:00") are rejected.

export declare function isValidIanaTimezoneId(timezoneId: string): boolean;

Parameters

Returns

boolean