Convert Unix timestamps ↔ human-readable dates. Support for seconds, milliseconds, and timezones.
A Unix timestamp (also called Epoch time or POSIX time) represents the number of seconds since January 1, 1970, 00:00:00 UTC. Most APIs return timestamps in seconds; JavaScript typically uses milliseconds. This tool converts between both formats.
Unix epoch was chosen arbitrarily by Unix creators in 1970. It became the standard for timekeeping in Unix and POSIX systems. All timestamps are relative to this reference point.
Unix timestamps are always in UTC. When converting to a date, use the timezone selector to see the local time. When converting from a date, the input is treated in your browser's timezone.
Most Unix timestamps from servers and logs use seconds. JavaScript's Date.now() returns milliseconds. Multiply seconds by 1000 to get milliseconds, or divide by 1000 to get seconds.