Timestamp Converter
Convert Unix timestamps to and from human-readable dates
Converts between a Unix timestamp and a human-readable date and time, in both directions — edit either field and the other updates instantly, with both UTC and your local timezone shown side by side.
How it works
The two fields — Unix timestamp and a date/time picker — share one underlying date value; editing either one recalculates the other immediately. A seconds/milliseconds toggle affects only how the Unix field is interpreted and displayed, since the underlying date itself doesn't change.
Frequently asked questions
Does the timestamp default to right now?
Yes — the tool loads with the current date and time already filled in, so you can start from now and adjust, rather than starting from a blank or zero value.
How do I know if I should use seconds or milliseconds?
Unix timestamps are traditionally in seconds, but many programming languages and APIs (JavaScript's Date.now(), for instance) use milliseconds — if your converted date looks wildly wrong (like the year 1970 or a date far in the future), try switching the toggle.
What timezone is used?
Both are always shown: one labeled UTC, and one labeled with your browser's local timezone, so you don't have to guess which one you're looking at or do the conversion yourself.
What happens if I enter an out-of-range or invalid timestamp?
You'll get a specific inline error — for a non-numeric value, a timestamp outside JavaScript's representable date range, or an invalid date/time value — rather than a silently wrong result.
Is my data sent anywhere?
No — every conversion happens locally in your browser using standard JavaScript date handling. Nothing is uploaded.