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Unix Timestamp Converter

Convert Unix timestamps to dates and back, in seconds or milliseconds.

Free foreverRuns in your browserNo sign-up
Timestamp to date

Seconds or milliseconds are both detected automatically.

Date to timestamp

About the Unix Timestamp Converter

A Unix timestamp counts the seconds since 1 January 1970 (UTC), a simple way for computers to store a moment in time.

This tool converts a timestamp into a readable date in UTC, local and ISO 8601 formats, and converts a date back into a Unix timestamp in seconds and milliseconds.

It automatically detects whether your timestamp is in seconds or milliseconds, and everything runs in your browser.

Key features

  • Timestamp to UTC, local and ISO date
  • Date to Unix seconds and milliseconds
  • Auto-detects seconds vs milliseconds
  • One-click 'Now' button

How to use

  1. 1Enter a timestamp to see the matching date, or click Now.
  2. 2Or pick a date and time to get its Unix timestamp.
  3. 3Copy the value you need.

Frequently asked questions

Seconds or milliseconds?
Both work. The tool treats 13-digit numbers as milliseconds and shorter numbers as seconds, and shows both when converting a date.
What is the ISO 8601 format?
ISO 8601 is a standard date format like 2026-08-18T09:30:00.000Z, widely used in APIs and databases because it is unambiguous.