Unix Timestamp Converter
Converts Unix epoch values into ISO 8601, UTC and local time, and converts dates back into epoch values. A live counter shows the current epoch in both seconds and milliseconds, ready to copy.
The unit is detected automatically from the magnitude of the number, so you do not have to tell it whether a value is in seconds, milliseconds or microseconds.
How to use it
- Type or paste an epoch value, or any date string your browser can parse.
- Read the ISO 8601, UTC, local and relative representations, each with its own copy button.
- Press Use now to load the current timestamp, or copy the live counter directly.
How the unit is detected
A ten-digit value is seconds, a thirteen-digit value is milliseconds and a sixteen-digit value is microseconds. Those ranges do not overlap for any date between 1970 and the year 2286, so the detection is reliable in practice rather than a guess — and the unit it chose is always displayed so you can confirm it.
Because of that, 1735689600 and 1735689600000 resolve to the same instant, which is usually what you meant.
Frequently asked questions
Seconds or milliseconds — which is my timestamp?
- Ten digits is seconds, the Unix convention used by most backends and databases. Thirteen digits is milliseconds, which is what JavaScript's Date.now() returns. The tool detects and reports which it used.
What time zone is the local time shown in?
- Your browser's own time zone. The UTC and ISO 8601 values are absolute, so use those when sharing a timestamp with someone else.
Can I convert a date back into an epoch value?
- Yes. Paste an ISO 8601 string such as 2025-01-01T00:00:00Z, or most other common date formats, and the epoch values in both seconds and milliseconds are shown.