Unix Timestamp Converter

A Unix timestamp, or epoch time, is a single number for a moment in time: the seconds that have passed since the start of 1970 in UTC. Computers like it because it's compact, sorts correctly and has no time zone or daylight saving to get wrong.

Developers meet these numbers in API responses, database rows, JWT expiry claims and log files, and need to read them quickly. This converter shows the current timestamp live, converts any timestamp to UTC, ISO 8601 and your local time with a relative "3 days ago", and converts a date and time back to a timestamp in seconds or milliseconds.

Unix time counts seconds since 00:00:00 UTC on 1 January 1970, ignoring leap seconds. Most databases and APIs store seconds; JavaScript, Java and many logging tools use milliseconds, which is why the same moment can be 1735689600 or 1735689600000.

Timestamps have no time zone: the same number is the same instant everywhere, and only the readable form changes. Systems that store it in a signed 32-bit integer overflow after 2147483647, 03:14:07 UTC on 19 January 2038, the so-called Year 2038 problem.