How does it know if I gave seconds or milliseconds?

Length-based: 10 digits or fewer is treated as seconds; 13 is milliseconds.

What time zone does 'local' use?

Your browser's time zone, as set by your OS.

Are my timestamps uploaded?

No. Conversion runs in your browser.

Developer Tools

Unix Timestamp Converter

Convert Unix timestamps (seconds or ms) to ISO, UTC, local, and relative time.

Input (unix seconds, milliseconds, or ISO date)

Unix seconds1777233359
Unix milliseconds1777233359000
ISO 8601 (UTC)2026-04-26T19:55:59.000Z
UTC stringSun, 26 Apr 2026 19:55:59 GMT
Local timeSun Apr 26 2026 19:55:59 GMT+0000 (Coordinated Universal Time)
Relativenow

Files processed in your browser

Your files never leave your device. No upload, no servers.

About Unix Timestamp Converter

Unix Timestamp Converter parses a unix timestamp (seconds or milliseconds — auto-detected) or an ISO date string, and shows it in every common format: ISO 8601, UTC, local time, and relative ("2 hours ago"). One-click copy each line. Useful for debugging timestamps in log files, converting epoch values from APIs, and quickly reading "what time was this event in my time zone".