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Unix Timestamp Converter

Convert a Unix timestamp — the number of seconds since January 1, 1970 at 00:00 UTC — into a readable date and time, or go the other way. Values in milliseconds are detected automatically.

Quick examples

Seconds or milliseconds — 13-digit values are read as milliseconds.

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Result2023-11-14 22:13:20 UTC
ISO 8601
2023-11-14T22:13:20Z
Seconds since epoch
1700000000
Milliseconds since epoch
1700000000000
Day of the week (UTC)
Tuesday

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      Formula

      Timestamp = seconds elapsed since 1970-01-01 00:00:00 UTC
      Milliseconds = seconds × 1000

      How to use it

      1. Choose the direction of conversion.
      2. Enter a timestamp, or a date and time in UTC.
      3. Copy the result in the form you need: seconds, milliseconds or ISO 8601.

      Worked examples

      Timestamp 1700000000

      Result
      2023-11-14 22:13:20 UTC
      Day of the week (UTC)
      Tuesday

      January 1, 2026 at 00:00 UTC

      Result
      1767225600
      Milliseconds since epoch
      1767225600000

      Seconds or milliseconds?

      Unix tools, most databases and languages such as Python and PHP use seconds: a 10-digit number today. JavaScript and Java use milliseconds: 13 digits. This converter treats values of 100 billion or more as milliseconds.

      The year 2038 problem

      Systems that store the timestamp as a signed 32-bit integer overflow after 2147483647, which is 03:14:07 UTC on January 19, 2038. Modern systems use 64-bit values and are unaffected.

      Questions people ask

      What is the Unix epoch?

      Midnight UTC at the start of January 1, 1970. Timestamp 0 is that instant; negative values are earlier.

      Does a Unix timestamp have a time zone?

      No. It counts seconds from a fixed instant, so it is the same everywhere. Time zones only matter when you display it as a local date and time.

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