Unix Timestamp Converter
Developer ToolsConvert Unix epoch seconds to dates and back.
Runs entirely in your browser — nothing is uploaded
Features
- Two-way conversion between epoch values and calendar dates.
- Detects seconds versus milliseconds automatically.
- Shows UTC, ISO 8601, local time and relative time together.
- A "now" button for the current timestamp.
How to use the Unix Timestamp Converter
- 1Paste an epoch number, or pick a date and time.
- 2Read every representation in the results panel.
- 3Copy whichever format you need.
Frequently asked questions
Seconds or milliseconds?
Unix time is seconds; JavaScript Date.now() returns milliseconds. Ten-digit values are seconds, thirteen-digit values are milliseconds — the tool detects this for you.
Why does the date not match what I expected?
Almost always a timezone difference. A Unix timestamp counts seconds from 1 January 1970 UTC and carries no timezone of its own, so the same number is a different wall-clock time in every location. UTC and your local time are shown together here precisely so that gap is visible rather than assumed.
What is the year 2038 problem?
Systems storing a timestamp in a signed 32-bit integer run out of room on 19 January 2038, when the count passes 2,147,483,647 and wraps round to a negative number, reading as 1901. Anything on 64-bit timestamps is unaffected, which includes JavaScript and every current database. It is a live concern mainly for old embedded hardware.
Why is the epoch 1 January 1970?
It was picked as a convenient recent starting point when Unix time was defined in the early 1970s, close enough to the present that a 32-bit count covered a useful span either side of it. There is no deeper meaning to the date. It simply stuck, and is now in more or less everything.