Unix Epoch & Timestamp Converter
Convert Unix timestamps in seconds or milliseconds to readable dates and back, with UTC and local views. Handles negative and large values.
Whole numbers only. Negative values are dates before 1970.
How it works
- Choose whether you are converting a timestamp to a date, or a date to a timestamp.
- Set the unit explicitly when a value is ambiguous — auto-detection is a guess, and the tool tells you which one it made.
- Both the UTC and your local rendering of the same instant are shown.
Frequently Asked Questions
Seconds or milliseconds?
Both. The tool guesses from the magnitude — ten digits is usually seconds, thirteen is usually milliseconds — but the guess can be wrong for small values, so an explicit unit selector is always available and the detected unit is shown.
Can it handle dates before 1970?
Yes. Negative timestamps count backwards from 1 January 1970, so -315619200 is 1 January 1960. Many converters reject or mangle these.
What is the largest timestamp supported?
Roughly ±8.64 x 10^15 milliseconds from 1970, about 273,000 years either side. Anything beyond that cannot be represented as a date, and the tool says so instead of showing an invalid result.
Why does a timestamp not include a timezone?
A Unix timestamp counts seconds since a fixed instant in UTC, so it has no timezone of its own. The timezone only matters when you display it, which is why both UTC and your local rendering are shown.