Unix Timestamp Converter
Convert Unix timestamps to readable dates and back, in any timezone.
About this tool
Converts Unix timestamps to dates and dates to timestamps, one per line, in whichever timezone you pick.
Seconds and milliseconds are detected by magnitude rather than assumed. This is where the real confusion lives: a millisecond timestamp read as seconds lands somewhere in the year 55000, and a seconds timestamp read as milliseconds lands in January 1970. Both are obvious once you see the date and invisible until then.
Common questions
What is a Unix timestamp?
The number of seconds since 1 January 1970 UTC. It has no timezone of its own — a timestamp is the same instant everywhere, and only becomes a local date when you choose one to display it in.
Seconds or milliseconds?
JavaScript uses milliseconds, most other systems use seconds. A ten-digit number is seconds; thirteen digits is milliseconds. This tool detects which by magnitude rather than assuming.
What is the 2038 problem?
A signed 32-bit timestamp overflows on 19 January 2038. Any system still storing timestamps in 32 bits will wrap to 1901. Modern PHP uses 64-bit integers, so this tool handles dates well beyond it.
Why does my date show an hour off?
Almost always daylight saving. A timezone is not a fixed offset — it is a set of rules about when the offset changes, so the same zone gives different results in January and July.