Convert Unix (epoch) timestamps in seconds or milliseconds to readable dates in UTC and your time zone, and dates back to timestamps.
A Unix timestamp counts the seconds since 00:00:00 UTC on 1 January 1970 (the epoch). JavaScript and many APIs use milliseconds instead; this converter detects which from the size of the number.
Timestamps are the same everywhere in the world. Only the displayed local time changes with your time zone.
Systems that store Unix time in a signed 32-bit number overflow on 19 January 2038. Modern systems use 64-bit time.