Unix Timestamp Converter

What a Unix timestamp is

It is the number of seconds since midnight on January 1, 1970, UTC. A single number pins down a moment in time with no time zone and no date format attached, which is why databases, logs, and API responses store time this way.

One field, both directions

Paste a number and get a date. Paste a date and get a number. The tool understands ISO 8601 with or without an offset, notation like 25.08.2026 14:30, the RFC 2822 format from email headers, and the output of Date.toString().

Seconds or milliseconds

This is the most common timestamp mix-up. You can tell the units by the length of the number:

• 10 digits — seconds;
• 13 digits — milliseconds;
• 16 digits — microseconds;
• 19 digits — nanoseconds.

In JavaScript, Date.now() returns milliseconds; in PHP, time() returns seconds; in Python, time.time() returns seconds with a fractional part.

The units are picked by the size of the number, and the result shows what the date would be in the other units. If the guess goes wrong, you can set the units manually.