Timestamp Converter
Convert between Unix timestamps and human-readable dates. Supports seconds, milliseconds, timezones, and relative time. Everything runs in your browser.
How it works: Enter a Unix timestamp or pick a date to convert between formats instantly. The tool auto-detects seconds vs milliseconds, shows relative time, and lets you view in any timezone. No data is sent to any server.
What is a Unix Timestamp?
A Unix timestamp (also called epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970 at 00:00:00 UTC — known as the Unix Epoch. It provides a universal, timezone-independent way to represent a point in time. Unix timestamps are widely used in programming, databases, APIs, and log files because they are simple integers that can be easily compared, stored, and transmitted.
Seconds vs Milliseconds
Traditional Unix timestamps count seconds since the epoch (10 digits, e.g., 1710288000). JavaScript, Java, and many modern APIs use milliseconds (13 digits, e.g., 1710288000000). This tool automatically detects which format you're using based on the number of digits, or you can manually toggle between seconds and milliseconds mode.
Working with Timezones
Unix timestamps are always in UTC — they represent an absolute moment in time regardless of timezone. When displaying a timestamp as a human-readable date, the timezone determines how it's shown. This tool lets you view any timestamp in any timezone using the browser's built-in Intl.DateTimeFormat API, supporting all IANA timezone identifiers.
Common Timestamp Formats
- Unix seconds — 10-digit integer (e.g., 1710288000)
- Unix milliseconds — 13-digit integer (e.g., 1710288000000)
- ISO 8601 — 2024-03-13T00:00:00.000Z (the web standard)
- RFC 2822 — Wed, 13 Mar 2024 00:00:00 +0000 (used in email headers)
- Relative time — '3 hours ago' or 'in 2 days' (human-friendly)