Convert Unix seconds, ms, µs or ns (auto-detected) to ISO 8601, RFC 2822 and any time zone, and back.

How it works

Paste a number and the unit is guessed from its digit count, which works for any date between 1973 and 5138:

Digits	Unit	Typical source
≤ 11	seconds	Unix `date +%s`, JWT claims, most APIs
12–14	milliseconds	JavaScript `Date.now()`, Java
15–17	microseconds	Python `time.time_ns() // 1000`, PostgreSQL
≥ 18	nanoseconds	Go `UnixNano`, Linux `CLOCK_REALTIME`, InfluxDB

Force a unit if the guess is wrong. Nanosecond inputs are handled exactly with BigInt; dates themselves have millisecond resolution.

You can also paste a date string (ISO 8601 like 2026-10-10T14:30:00Z is safest) to get its timestamp. Leave the field empty to see the current time, live.

References

Unix time — Wikipedia
RFC 3339 — Date and Time on the Internet

Unix Timestamp Converter

How it works

References

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