Unix timestamp converter
Convert seconds, milliseconds and ISO dates.
Unix timestamp converter
How to use Unix timestamp converter
Unix timestamp converter turns an epoch timestamp into an ISO 8601 date, or a date into epoch seconds and milliseconds. Output also includes the local time in this computer's time zone and states how the input was read. Automatic mode treats values of 100,000,000,000 or more as milliseconds, and you can force seconds or milliseconds.
- Paste the source into the input editor, or load the built-in example.
- Set timestamp unit.
- Run unix timestamp converter, review the output, then use the available copy or download controls.
What this tool supports
Automatic mode reads a number of 100,000,000,000 or more as milliseconds and a smaller number as seconds. An ISO 8601 date is read as a date. The result names the unit and this computer's time zone.
- Timestamp unit
- Automatic · Seconds · Milliseconds
Limits and processing
Text operations generally accept up to 2,000,000 characters. Individual parsers, generators and formulas apply additional limits shown by their controls.
Example source
2026-09-29T12:00:00Z
Frequently asked questions
How do I convert a Unix timestamp to a date?
Paste the number and run the tool. The result lists the ISO 8601 time in UTC, the equivalent seconds and milliseconds, and the local date and time in your computer's time zone.
Is my timestamp in seconds or milliseconds?
In Automatic mode, an absolute value of 100,000,000,000 or more is read as milliseconds and anything smaller as seconds. Choose Seconds or Milliseconds to override that guess.
Can I convert a date to a Unix timestamp?
Yes. Enter an ISO 8601 date with a time zone, such as 2026-09-29T12:00:00Z, and the result shows the matching epoch seconds and milliseconds.
Where is my input processed?
This operation processes its source in your browser. Copy and download are explicit actions; source input is not saved in an account or history.
What are the input limits?
Text operations generally accept up to 2,000,000 characters. Individual parsers, generators and formulas apply additional limits shown by their controls.