Unix Timestamp Converter
Convert between a Unix timestamp (seconds since 1970-01-01 UTC) and an ISO 8601 date. Runs entirely in your browser.
How it works
A Unix timestamp counts whole seconds elapsed since 1970-01-01T00:00:00Z (the "Unix epoch"), independent of timezone. Negative values represent dates before 1970. Results are always shown in UTC.
Examples
| Timestamp | Date (UTC) |
|---|---|
0 | 1970-01-01T00:00:00Z |
86400 | 1970-01-02T00:00:00Z |
-86400 | 1969-12-31T00:00:00Z |
FAQ
Milliseconds or seconds? This tool uses seconds, the standard Unix
timestamp unit. JavaScript's own Date.now() returns milliseconds — divide
by 1000 first if converting from that.
What if I enter an absurdly large or negative timestamp? You'll get a clear error instead of a technically-valid but meaningless date thousands of years away.