Unix Timestamp Converter
Convert Unix timestamps to dates and back, in your browser.
What this tool does
Unix Timestamp Converter turns epoch numbers into readable dates and back again, right in your browser. It shows the current Unix time live, converts in both directions, and displays each result in UTC, your local time zone, and ISO 8601.
How to use
- Paste a Unix timestamp to see it as a date, or use the current time.
- Leave the unit on auto-detect — 10-digit values are read as seconds, 13-digit as milliseconds.
- Read the result in UTC, local time, ISO 8601, or as a relative time.
- To go the other way, fill in the date fields and copy the timestamp.
Notes
- Everything is computed in your browser — no request is made to a server.
- Date fields are interpreted as UTC; the local-time row shows your browser's offset.
- Unix time counts seconds since 1970-01-01 UTC and ignores leap seconds.
Frequently asked questions
Seconds or milliseconds — how do I tell?
A 10-digit timestamp is in seconds (the Unix standard), while a 13-digit one is in milliseconds (what JavaScript's Date.now() returns). Auto-detect uses that length rule, and you can always set the unit manually.
Why does the date differ from what I expected?
Most likely a time-zone difference. The UTC row is the canonical value; the local row is converted to your browser's time zone, so the two differ by your UTC offset.
Can I convert dates before 1970?
Yes. Timestamps before the epoch are negative — for example, -86400 is 1969-12-31 UTC. Just include the minus sign.
What is the year 2038 problem?
Systems that store Unix time in a signed 32-bit integer overflow on 2038-01-19, after which the value wraps to a negative number. This tool uses 64-bit floating point numbers, so it handles dates far beyond 2038.