Unix Timestamp Converter

What this tool does

A Unix timestamp counts the number of seconds that have elapsed since midnight UTC on January 1, 1970 (the "Unix epoch"), and it's the standard way computers store and exchange points in time internally. This tool converts a timestamp into a human-readable date in both your local timezone and UTC, or works in reverse: pick a date and time and get back the equivalent Unix timestamp in seconds and milliseconds. Everything runs locally using your browser's own clock and timezone settings.

Example use case

Developers debugging an API response, a database row, or a log line often see a raw number like 1735689600 instead of a readable date, and need to know what date that actually represents in their own timezone. Going the other direction is just as common — picking a specific date to test against, like generating a timestamp for "30 days from now" to check an expiration condition.

Seconds vs. milliseconds

Unix timestamps are traditionally expressed in seconds, but JavaScript's Date.now() and many web APIs use milliseconds instead. This tool reports the timestamp in both, so you can tell at a glance which one your system expects — a value with three extra trailing digits is almost always milliseconds, not seconds.