Unix Timestamp Converter
Convert a Unix timestamp to a readable date and back. Shows UTC and local time side by side. All processing happens in your browser; your input is never sent to the server.
A Unix timestamp counts seconds since 1 January 1970 UTC. It is compact and timezone-free, which is exactly why logs, APIs and databases use it — and exactly why it is unreadable to humans. This converter goes both ways and shows UTC, your local time and a plain-language relative time side by side.
How to use it
- Paste a timestamp into the left field. Ten digits are read as seconds, thirteen as milliseconds — the tool detects which.
- Or pick a date in the right field to convert in the opposite direction.
- Read the output block: seconds, milliseconds, ISO 8601, UTC, your local time, and how long ago it was.
- Press Now to stamp the current moment when you just need a value to paste.
Frequently asked questions
- Seconds or milliseconds — how do I tell?
- Length. A ten-digit number is seconds, a thirteen-digit number is milliseconds. Mixing them is the single most common bug in this area and puts your date roughly fifty thousand years off.
- Why does the local time differ from a colleague's?
- The timestamp itself has no timezone. Local time is rendered using your device settings, so two people converting the same value correctly see different wall-clock times.
- What is the 2038 problem?
- Systems storing the timestamp in a signed 32-bit integer overflow on 19 January 2038. Anything using 64-bit integers, including JavaScript, is unaffected.
- Does it handle dates before 1970?
- Yes. Timestamps before the epoch are negative, and the converter accepts them.