Unix Timestamp Converter

Convert Unix timestamps and dates, individually or in batches. Confirm the time zone, inclusivity of start and end dates, and any local holidays that matter.

Your text is processed locally in a browser worker. It is not uploaded by this tool or saved in browser storage. Clear releases the working input and result. Downloads remain in your normal download folder.

It measures elapsed time from 1 January 1970 at 00:00:00 UTC. Different systems use seconds or milliseconds, so you must select the correct unit. Negative values refer to earlier dates.

A local clock time can occur twice when daylight saving ends, or not occur when it starts. We require Z or an explicit offset such as +01:00 instead of guessing. The offset you supply is used as written; the tool does not verify that it matches a particular city on that date.

No. Copied and downloaded dates are always UTC ISO dates, ending in Z. Timestamp output uses your chosen unit. The comparison table displays the first 100 valid entries using your browser’s timezone data, which may differ for historical dates or future rule changes.

Dates from years 0001 to 9999 in UTC, with millisecond precision. Seconds may have up to three decimal places; milliseconds must be whole numbers. Invalid calendar dates, ambiguous date formats, leap seconds and finer precision are rejected. This follows the browser’s time-value model, with a deliberately narrower date range.

They are replaced by line-numbered error messages in the results. Blank lines and ordering are preserved. Those messages are included in copy and download, so correct errors before passing the output into another system. Up to 5,000 lines and 300,000 characters can be processed per batch.