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Unix Timestamp Converter — Seconds, Milliseconds & UTC
Decode a timestamp from an API response, event log or scheduled task. Choose seconds or milliseconds explicitly, or enter a calendar time in UTC to obtain both numeric representations.
Calculations run in your browser. No account or API key is needed.
Your result
- UTC date and time
- 2026-01-01T00:00:00.000Z
- Unix seconds
- 1767225600
- Unix milliseconds
- 1767225600000
UTC date and time: 2026-01-01T00:00:00.000Z Unix seconds: 1767225600 Unix milliseconds: 1767225600000
How to use this tool
Choose timestamp-to-date or UTC-date-to-timestamp conversion.
Complete the input for that direction; select the timestamp unit if needed.
Run the converter and compare the ISO UTC date, seconds and milliseconds.
A unit mismatch can look like a date bug
A modern timestamp in milliseconds is much larger than one in seconds. Never infer the unit only from its digit count: values near the epoch can be short, and older dates may be negative. Check the source API documentation.
UTC keeps the result reproducible
The result uses a trailing Z to identify UTC. The calendar input is also interpreted as UTC, regardless of your computer’s timezone. Convert your intended local time to UTC first if you are planning an event in a particular city.
Common questions
Are negative timestamps supported?
Yes. They represent instants before 1970-01-01T00:00:00Z. Millisecond input retains its fractional-second result.
Why was my date rejected?
Impossible calendar dates, leap seconds and values outside the supported Date range are rejected rather than silently shifted to another day.