ISO 8601 Timestamp Validator and Formatter

Validate ISO 8601 timestamps and normalize formatting for APIs, JSON payloads, audit logs, schedules, feeds, and database exports. Use it to catch malformed dates before they break integrations or create timezone confusion. ToolMill runs fully client-side, which makes it convenient for checking production-like values without sending them to another validator service.

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ISO 8601 timestamp or date

Validation result

Examples

Full UTC timestamp

Input

2026-03-05T17:46:39Z

Output

Valid ISO 8601 UTC timestamp

Date only

Input

2026-03-05

Output

Valid ISO 8601 date

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