🕐 Timestamp Converter

Convert between Unix timestamps and human-readable dates

✓ Free Forever · ✓ No Signup · ✓ No Upload · ✓ Works Offline

🔒 Your data never leaves your device. All processing happens locally in your browser using JavaScript Date API. No upload, no server, no tracking.

Features

  • Unix Timestamp Conversion — Seconds, milliseconds, microseconds or nanoseconds, read by length — or set the unit yourself. Dates go the other way.
  • Local & UTC Time — UTC and your browser's time zone side by side, with the offset that applied on that date.
  • ISO 8601 Format — ISO 8601 in UTC and with your own offset, plus the HTTP date form.
  • Relative Time — See how long ago or in the future a timestamp is.

How It Works

  1. Type or paste a timestamp or date — A Unix number in any unit, an ISO 8601 or RFC 2822 date — or pick one with the date picker.
  2. View all formats — See the timestamp in Unix, ISO 8601, local time, UTC, and relative format.
  3. Copy what you need — Press Copy next to any format.

Use Cases

  • Debug API timestamps in logs and responses
  • Convert database timestamps to readable dates
  • Calculate time differences between events

Frequently Asked Questions

Does it support millisecond timestamps?

Yes — and microseconds and nanoseconds. A number is read by its length: up to 11 digits = seconds, 12–14 = milliseconds, 15–17 = microseconds, 18 or more = nanoseconds. The line under the box says which unit it used, and you can pick another (a millisecond value from before March 1973 has only 11 digits, for example). Browsers keep time to the millisecond, so finer digits are dropped and the page says so.

What timezone is used?

A Unix timestamp has no time zone: it counts seconds since 1 January 1970, 00:00 UTC. The page shows that moment in UTC and in your browser's time zone, using the offset that applied on that date (summer and winter differ where clocks change). The date picker works in your local time.

Can I paste a date instead of a number?

Yes: ISO 8601 (2023-11-14T22:13:20Z, with an offset like +08:00, or a space instead of the T) and the RFC 2822 form used in HTTP and email headers (Tue, 14 Nov 2023 22:13:20 GMT). A date without a time zone is read as your local time, and the page tells you so.

What about dates before 1970?

Type a negative number: -86400 is 31 December 1969, 00:00 UTC. Any date a browser can hold works, from 271,821 BC to AD 275,760.

Notes from Milo 🐨

2026-10-07

The page promised it would tell seconds from milliseconds on its own. It didn't: paste 1700000000000 from a log and it showed the year 55840. Now a number is read by its length (seconds, milliseconds, microseconds or nanoseconds), the line under the box says which, and you can override it. You can also paste a date (2023-11-14T22:13:20Z, or an HTTP-style date) to get the timestamp, type negative numbers for dates before 1970, and see ISO 8601 with your own offset. The how-it-works and FAQ section also vanished the moment the page loaded. It's back. And Copy no longer says "Copied!" when your browser blocked it.

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💬 Bug, idea, or just to say hi? Tell Milo 🐨 · [email protected]