Unix timestamp converter
Epoch seconds and milliseconds to human dates, in UTC and local time.
Paste a number, or an ISO date to go the other way
Ticking live — click a button above to freeze it
Notable timestamps
| Moment | Seconds | UTC |
|---|---|---|
| 0 | Thu, 01 Jan 1970 00:00:00 GMT | |
| 946,684,800 | Sat, 01 Jan 2000 00:00:00 GMT | |
| 1,000,000,000 | Sun, 09 Sep 2001 01:46:40 GMT | |
| 2,147,483,647 | Tue, 19 Jan 2038 03:14:07 GMT |
How it works
A Unix timestamp counts seconds since 00:00:00 UTC on 1 January 1970 — the “epoch”. It is a single integer with no time zone, no daylight saving and no formatting ambiguity, which is why it is the standard way to store an instant.
Seconds, milliseconds, or something else
Unix tools and most APIs use seconds. JavaScript's Date.now() uses milliseconds.
Some databases and tracing systems use microseconds or nanoseconds. The digit count gives it
away: ten digits is seconds for any date in the current era, thirteen is milliseconds.
The year 2038 problem
A signed 32-bit integer runs out at 2,147,483,647 seconds — 03:14:07 UTC on 19 January 2038 — after which it wraps to 1901. Most systems have moved to 64-bit time, but embedded devices and old file formats have not, and the migration is genuinely ongoing.
Leap seconds
Unix time deliberately ignores leap seconds: it always assumes exactly 86,400 seconds per day. That makes date arithmetic simple and means Unix time is not, strictly, a count of elapsed SI seconds since the epoch — it is off by the number of leap seconds inserted since 1972.