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Date And Time

Unix Timestamp Converter

Convert a Unix timestamp to a human-readable date and time, or go the other way. Supports multiple timezones and output formats.

Current Unix time

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How it works

A Unix timestamp is the number of seconds (or milliseconds) that have elapsed since the Unix epoch: midnight UTC on January 1, 1970. It is a single integer — timezone-agnostic, unambiguous, and easy to compare and sort.

This tool uses the browser's built-in Date object and the Intl.DateTimeFormat API to convert timestamps to local and UTC representations. All calculations happen in your browser.

Common uses

  • API debugging — most REST APIs return created_at, expires_at, and updated_at as Unix timestamps
  • Log analysis — syslog, Nginx, and application logs often use Unix time
  • JWT tokens — the exp and iat claims in JWTs are Unix timestamps in seconds
  • Database timestamps — many databases store dates as integers for indexing efficiency

🔒 Privacy

All conversions happen in your browser. No timestamps or dates are sent to any server.

Edge cases and limits

  • Negative timestamps — values before 1970 are supported (e.g. -86400 = Dec 31, 1969).
  • Milliseconds vs seconds — a common mistake is pasting a millisecond timestamp into seconds mode. If you get a date in the year ~50000, switch to milliseconds.
  • Daylight saving time — the timezone selector uses IANA timezone names, so DST transitions are handled correctly.
  • Far future dates — JavaScript's Date supports dates up to ~Sep 13, 275760.

FAQ

Why does Unix time start in 1970?

The Unix epoch (Jan 1, 1970 UTC) was chosen when Unix was being developed in the late 1960s. It was a convenient, recent date that fit in a 32-bit integer for decades. The 32-bit overflow ("Year 2038 problem") affects systems that store timestamps as signed 32-bit integers.

What is ISO 8601?

ISO 8601 is an international standard for date/time representation. It looks like 2024-05-04T12:00:00Z. The trailing Z means UTC. It is sortable as a string and widely supported in APIs and databases.

Seconds vs milliseconds — how do I tell?

A seconds timestamp in 2024 is 10 digits (e.g. 1714867200). A milliseconds timestamp is 13 digits (e.g. 1714867200000). If your value is 13 digits, use milliseconds mode.

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