Unix Timestamp Converter
Convert between a Unix timestamp and a date/time, in either direction.
Timestamp → Date
Date → Timestamp
A date/time picker never carries timezone info by itself — choose explicitly which one you mean.
Converted locally. Your data never leaves your browser.
Common questions
Why do I have to specify seconds vs. milliseconds instead of it being detected automatically?
Because the same number means a wildly different date depending on which unit it is, and guessing from its magnitude would risk silently misinterpreting your input. The unit is always explicit here, never inferred.
What happens if I enter an invalid calendar date, like February 30?
It's rejected with an error, rather than silently rolling over to March 2 the way JavaScript's Date object does internally — the date you typed is checked against the real calendar before being accepted.
Is there a limit to which timestamps can be converted?
Only the practical range a JavaScript date can represent (roughly ±273,000 years from 1970) — a timestamp outside that range shows a clear error rather than a garbled or incorrect date.