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Unix timestamp converter

Convert Unix timestamps in your browser: nothing is uploaded, there is no limit on the number of lines, and you can paste a whole column at once. Seconds and milliseconds are told apart automatically.

Timestamp unit
Time zone
Write the date as

How it works

  1. Paste your code

    Paste the code in the left box or open a file. No code to hand? Click Example.

  2. Instant result

    The result appears as you type. If there is an error, you see the line and character.

  3. Copy or download

    Copy the result with one click or save it as a file for your editor or project.

What is a Unix timestamp?

A Unix timestamp (or epoch time) is the number of seconds since 1 January 1970 at 00:00 UTC. For example, 1790000000 is Monday 21 September 2026 at 14:13 UTC. Computers use it because it is a single number, without time zones or daylight saving time. JavaScript and Java count in milliseconds (13 digits), most other systems in seconds (10 digits). With Automatic the tool tells them apart by size; microseconds and nanoseconds are recognised too.

Which dates are recognised?

  • 2026-09-27, 2026-09-27 14:30 or 2026-09-27T14:30:00Z (ISO 8601)
  • 27-09-2026 or 27-09-2026 14:30 (day first)
  • English formats such as Sun, 27 Sep 2026 12:00:00 GMT

A date without a time zone is read in the chosen zone: My time zone (your device's, including daylight saving time) or UTC. If the date includes a zone, such as Z or +02:00, that one is used.

The year 2038 problem

Older systems store the timestamp as a 32-bit number. That overflows on 19 January 2038 at 03:14:07 UTC (timestamp 2147483647). Modern systems use 64 bits and are not affected.

Seconds or milliseconds?

If a timestamp has 10 digits it is in seconds, with 13 digits it is in milliseconds. A date in 1970 means you read milliseconds as seconds, and a date in the year 50,000 means the other way around. Automatic mode picks by size, but you can force the unit when you know it.

Doing it in code

  • JavaScript: new Date(ts * 1000) for seconds, new Date(ts) for milliseconds; Math.floor(Date.now() / 1000) for now.
  • Python: datetime.fromtimestamp(ts, tz=timezone.utc).
  • SQL: FROM_UNIXTIME(ts) in MySQL, to_timestamp(ts) in PostgreSQL.
  • Shell: date -d @1790000000 on Linux, date -r 1790000000 on macOS.

Time zones and daylight saving

A timestamp has no time zone: it is always the same instant everywhere. Only the display depends on a zone. When you debug something that "is one hour off", check whether the date was read as local time or as UTC, and whether daylight saving time began or ended in between.

Dates before 1970 are negative timestamps, and they work here. For decoding the timestamps inside a token, see the JWT decoder.

See also: JWT decoder · JSON formatter.

Frequently asked questions

How do I know if a timestamp is in seconds or milliseconds?

Ten digits is seconds, thirteen is milliseconds. Automatic mode chooses by size.

Why is my date in 1970?

The value was probably in milliseconds but read as seconds, or the other way around. Switch the unit.

What is the year 2038 problem?

Systems that store the timestamp in a signed 32-bit number overflow on 19 January 2038. Modern 64-bit systems are not affected.

Is my data uploaded?

No. Everything is converted in your browser.