Convert seconds or milliseconds to ISO dates, or turn a local or offset ISO date back into a timestamp.

Unix Timestamp Converter

Choose a browser or common IANA time zone for an ISO value without an offset. Results always show UTC, browser-local and selected-zone times; explicit ISO offsets take priority and DST edge cases are explained.

How to use this tool

  1. Enter a Unix timestamp and choose Auto, seconds or milliseconds, or enter an ISO date and time.
  2. Use the browser time zone, UTC, or search a common IANA time zone when the ISO value has no offset.
  3. Review UTC, local, selected-zone and Unix values, then copy one value or the complete local result.

Frequently asked questions

Which time zone is used for an ISO value with Z or an offset?

An explicit Z or numeric offset is used exactly as entered. The selected IANA time zone is used only when the input has no offset.

How are daylight-saving changes handled?

Skipped local times are rejected. When a local wall time occurs twice, the earlier instant is selected and the result explains that choice.