Free Unix Timestamp Converter — Epoch, ISO & Human Time
Logs store 1757328000, APIs return 2026-09-08T12:00:00Z, and humans need "Monday noon" — this free converter translates between all three instantly, in both directions, with UTC, local, ISO 8601, and relative ("3 days ago") readings for every value.
How to Convert
- Paste a 10-digit value for Unix seconds, 13-digit for milliseconds (auto-detected), or any ISO date string.
- Click Convert — UTC, local timezone, ISO, and relative phrasing appear together, so copy whichever your context needs.
- Going the other way? type a date like
2026-12-25 08:00to get its epoch values for code and databases.
Seconds vs Milliseconds vs ISO
Classic Unix time counts seconds since 1970-01-01 UTC (10 digits until the year 2286); JavaScript's Date.now() returns milliseconds (13 digits) — the single most common conversion bug in web development. ISO 8601 strings are human-readable and unambiguous across timezones when suffixed with Z. The auto-detector here uses digit length, so pasting either numeric form just works.
Why is my timestamp off by hours?
Almost always a UTC-vs-local mixup: the database stored UTC while your code formatted local time (or vice versa). Compare both readings this tool shows to spot the shift immediately.
What is the Year 2038 problem?
Signed 32-bit seconds overflow in January 2038. Modern 64-bit systems and millisecond timestamps are unaffected — one more reason to prefer 64-bit and ISO formats in new code.
Is my data uploaded?
No — Date.parse and formatting run locally in your browser.
Related Tools
Decode token timestamps with the JWT Decoder, schedule across zones with the Time Zone Converter, and plan meeting times with the Age Calculator.