Timestamp Converter

Seconds, milliseconds, microseconds

The digit count usually gives the unit away: 10 digits are seconds, 13 are milliseconds, and 16 are microseconds. Unix tools, Python's time.time(), and JWT expiry times use seconds; JavaScript's Date.now() and Java use milliseconds. A date in 1970 or tens of thousands of years ahead is the classic sign of a unit mix-up.

Time zones and ISO 8601

A Unix timestamp has no time zone: it is the same instant everywhere. Time zones only enter when it is shown as a date. For stored and exchanged dates, ISO 8601 with an explicit offset, such as 2026-03-29T09:30:00Z or 2026-03-29T11:30:00+02:00, avoids the ambiguity of a bare local time, which can be missing or repeated on the days clocks change.

The year 2038

Systems that store Unix seconds in a signed 32-bit integer overflow at 03:14:07 UTC on 19 January 2038 and wrap round to 1901. Most current platforms use 64-bit time, but embedded devices, old file formats, and database columns can still carry the limit.

How to use it

1. Enter Unix seconds, Unix milliseconds, or a date string.
2. Convert the value.
3. Compare the exact instant across common timestamp formats.

Privacy & limitations

Conversion runs locally. Date strings without an explicit timezone may be interpreted in your browser’s local timezone.