What Unix time is, why it is counted from 1970, how to convert it, and why it will eventually have a Year 2038 problem.
What Unix time is
The number of seconds since 00:00:00 UTC on 1 January 1970, not counting leap seconds. Same value everywhere in the world.
Why 1970?
It was a convenient round number when Unix was being developed in the early 1970s. It became the industry standard.
Seconds vs milliseconds
JavaScript and some Java APIs use milliseconds. Most Unix systems use seconds. The numbers differ by 1000×.
The Year 2038 problem
Systems storing Unix time as signed 32-bit integers will overflow on 19 January 2038. Modern 64-bit systems are safe for billions of years.
Convert instantly
Use our free Unix Timestamp Converter.