OpenGPT.in

Timestamp Converter

Convert Unix timestamps to dates, and back.

Runs in your browser Runs entirely in your browser. Nothing you put in it ever leaves your device.

Timestamp to date

Seconds, milliseconds or microseconds — detected from the length.

UTC
Local time
ISO 8601
Relative
Read as

Enter a timestamp to convert it.

Date to timestamp

Interpreted in your local time zone.

Seconds
Milliseconds
ISO 8601 (UTC)

Your time zone:

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About this tool

Paste a timestamp and see it in UTC, your local time zone and ISO 8601 — or pick a date and get the epoch value back. Seconds, milliseconds and microseconds are detected automatically from the number of digits.

How to use it

  1. Paste a Unix timestamp, or press “Now”.
  2. Read it off in UTC, local time, ISO 8601 and relative form.
  3. Or switch to the date side and enter a date to get the timestamp.

Supported input

  • Seconds
  • Milliseconds
  • Microseconds
  • ISO 8601 date strings

Privacy

Runs entirely in your browser. Nothing you put in it ever leaves your device. Everything happens in JavaScript on this page, so the tool keeps working even if you go offline after it has loaded — which is the simplest way to see for yourself that nothing is being sent. Read the full privacy information.

Questions

How does it know whether my number is seconds or milliseconds?

By its length. Ten digits is read as seconds, thirteen as milliseconds and sixteen as microseconds — and you can always override the unit if the guess is wrong.

Which time zone is used?

Both: every result is shown in UTC and in the time zone your browser reports, so you never have to do the arithmetic yourself.

Does it handle dates before 1970?

Yes. Negative timestamps are valid and are converted normally.