Date, time, and ID validators
Use Date-Time Format Validator for parseable timestamps; ISO Compliance Checker is a stricter sibling of the same job. UUID and ID collision tools belong with identifiers, not with JSON. Cron explainer is read-only documentation of a five/six-field expression.
Format Checker is a kitchen-sink regex for email/URL/UUID/semver — bookmark the dedicated URL, IP, or UUID page when you know the type. Timestamp Converter does not implement webhook replay windows; Replay Tester in the API hub does.
Dates, timestamps & cron(4)
Date-Time Format ValidatorValidate date-time strings (ISO 8601, RFC 2822). Get parsed result in ISO format.ISO Compliance CheckerCheck if a date-time string is strictly ISO 8601 compliant. Get violations and parsed result.Timestamp ConverterConvert Unix timestamp (seconds or ms) to ISO date-time and vice versa.Cron Expression ExplainerHuman summary plus next run times from a cron expression (cron-parser + cRonstrue).
UUIDs & IDs(2)
Multi-format check(1)
FAQ
- Why is my locale date rejected?
- Strict ISO/RFC parsers reject 12/31/2025 style strings. Convert to ISO-8601 or use Timestamp Converter for Unix seconds/millis.
- Are UUID checks RFC 4122 version-aware?
- The generator/validator checks canonical hex form and version/variant bits we document on the tool page. Nil UUID is called out separately.