This free Unix timestamp converter converts between Unix epoch time and human-readable dates in either direction. Watch the current timestamp update live, convert any timestamp in seconds or milliseconds to a local date, ISO 8601, and UTC string, or pick a date and time to get its equivalent Unix timestamp.
Common uses: debugging API responses, setting cache expiry values, working with database created_at / updated_at fields, and scheduling logic. Everything runs client-side — no timestamps ever leave your browser.
Frequently Asked Questions
What is a Unix timestamp?+
A Unix timestamp, also called Unix time or epoch time, is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC — known as the Unix epoch. It's a simple integer that represents a moment in time independent of timezone or calendar formatting, which is why it's so widely used in programming.
Why do some timestamps have 13 digits instead of 10?+
A 10-digit timestamp is in seconds; a 13-digit timestamp is in milliseconds (seconds × 1000). JavaScript's Date.now() and many JSON APIs return milliseconds, while Unix and Linux system tools typically use seconds. This converter automatically detects which unit you've entered.
What is the Year 2038 problem?+
Systems that store Unix time as a signed 32-bit integer will overflow on January 19, 2038 at 03:14:07 UTC (timestamp 2147483647), wrapping around to a negative number and effectively resetting to 1901. Most modern systems now use 64-bit integers, which push that limit tens of billions of years into the future.
Does Unix time account for timezones?+
No — a Unix timestamp always represents an absolute moment in UTC, with no timezone attached. Timezone only matters when you convert that timestamp into a human-readable date; this tool displays the result in both your local timezone and UTC so you can compare.
How is Unix time different from ISO 8601?+
Unix time is a single integer (seconds since the epoch) with no built-in formatting, while ISO 8601 (e.g. 2026-07-21T12:40:15Z) is a human-readable, sortable string format that includes the date, time, and often a timezone offset. APIs frequently use one or the other, so this tool converts between both.
What is epoch time actually used for?+
It's used anywhere software needs a compact, unambiguous way to store a point in time: database timestamp columns, JWT iat/exp claims, cache expiration, log entries, cookie expiry, and cron or scheduling systems all commonly store time as a Unix timestamp.