How to use the Timestamp Converter

Left panel: enter a Unix timestamp (in seconds or milliseconds) and get the equivalent date in local time, UTC, and ISO 8601 format, plus a relative description ("3 days ago").
Click Now to fill in the current timestamp instantly.
Right panel: pick a date and time to get the equivalent Unix timestamps in seconds and milliseconds.

What is a Unix timestamp?

A Unix timestamp is the number of seconds (or milliseconds) elapsed since the Unix epoch: midnight on 1 January 1970 UTC. Timestamps are timezone-agnostic: the same number represents the same instant everywhere in the world. This makes them ideal for storing dates in databases and APIs, where converting to the user's local time happens at display time.

Seconds vs milliseconds

Most Unix systems and databases use seconds (10-digit numbers, e.g. 1700000000). JavaScript's Date.now() and many modern APIs use milliseconds (13-digit numbers, e.g. 1700000000000). This tool auto-detects which unit you pasted based on the number of digits.

Common use cases

Reading API responses: REST APIs often return creation and modification times as Unix timestamps
Debugging logs: server logs typically use Unix time; convert them to human-readable dates
Database queries: check whether a stored timestamp is in the past or future
Scheduling: compute the timestamp for a future date when setting up timed jobs

ISO 8601 format

ISO 8601 is the international standard for date/time representation: 2024-11-15T00:00:00Z. The trailing Z means UTC. It is unambiguous across locales (unlike "11/15/24" which means different things in the US and Europe) and sorts lexicographically in chronological order.