Unix Timestamp Converter
Epoch ⇄ human-readable dates, seconds or milliseconds.
Timestamp → Date
Date → Timestamp
Why Unix timestamps exist
A Unix timestamp is the number of seconds elapsed since 1970-01-01 00:00:00 UTC. It is how nearly every database, API and log stores time: timezone-free, unambiguous and trivially sortable. The cost is that humans cannot read it — hence this converter.
Auto-detect treats values under 100 billion as seconds and larger ones as milliseconds, which covers the two conventions you will meet in APIs. The date output shows both your local timezone and UTC so you can spot off-by-timezone bugs immediately.
When converting a date into a timestamp, the input is interpreted in your browser's local timezone — the same behavior as most programming languages' date constructors.
FAQ
Is the timestamp affected by my timezone?
The numeric timestamp itself is absolute UTC. Only the display conversion depends on your local timezone — the same number is the same moment everywhere on Earth.
What happens in 2038?
The Y2038 problem affects systems storing timestamps as signed 32-bit integers, which overflow in January 2038. Modern 64-bit systems and most current frameworks are unaffected.
Why does my API return 13-digit timestamps?
Many JavaScript ecosystems use milliseconds instead of seconds (Date.now() returns milliseconds). Auto-detect handles both.