Unix Timestamp Converter
Convert whole Unix seconds into a UTC timestamp.
Result for the values shown.
Calculations run in your browser.
What to enter
| Input | Meaning and units |
|---|---|
| Seconds | Include seconds and an explicit Z or UTC offset, for example 2024-01-01T12:00:00Z. At most three fractional-second digits. |
Understanding your result
The timestamp is expressed in whole Unix seconds from the UTC epoch, not milliseconds. The displayed date/time is UTC.
Common mistakes
- Entering a millisecond timestamp where seconds are requested.
- Reading UTC output as local clock time without applying an offset.
Check your calculation
- Zero Unix seconds corresponds to 1970-01-01T00:00:00Z.
Calculation checks, sources and review limits
What UTC date and time does a Unix timestamp in seconds represent?
Convert whole Unix seconds into a UTC timestamp.
Common uses
- Convert whole Unix seconds into a UTC timestamp.
How it works
Unix seconds count from 1970-01-01T00:00:00Z; this tool converts seconds to UTC, excluding leap seconds. Supported UTC years are 0001 through 9999. Enter seconds, not milliseconds. Calendar arithmetic uses the proleptic Gregorian calendar. Explicit calendar dates are independent of local daylight-saving changes. Month/year additions clamp to the last valid day of the destination month. Timestamp arithmetic requires a stated UTC offset and excludes leap seconds.
Worked example
Enter Seconds: 0. The result is Seconds: 0; Utc: 1970-01-01T00:00:00Z.
FAQ
What UTC date and time does a Unix timestamp in seconds represent?
Unix seconds count from 1970-01-01T00:00:00Z; this tool converts seconds to UTC, excluding leap seconds. Supported UTC years are 0001 through 9999. Enter seconds, not milliseconds. Calendar arithmetic uses the proleptic Gregorian calendar. Explicit calendar dates are independent of local daylight-saving changes. Month/year additions clamp to the last valid day of the destination month. Timestamp arithmetic requires a stated UTC offset and excludes leap seconds.
What assumptions and limits apply?
Explicit seconds/milliseconds selector; UTC, no leap seconds; JS Date range and 0..99 year constructor pitfalls.