Convert both ways: readable date → Unix timestamp and Unix timestamp → readable date, with a choice of time zone (local or UTC) and granularity (seconds or milliseconds).
| Local time | |
|---|---|
| UTC | |
| ISO 8601 | |
| Relative to now |
The Unix timestamp (or epoch time) is the number of seconds elapsed
since January 1st, 1970 at 00:00:00 UTC, not counting leap seconds.
It is the most common way to represent an instant in time in computer systems, because it is
just an integer — easy to store, compare and transmit, and independent of time zone. Many
systems use milliseconds instead of seconds (JavaScript's Date.now(),
for example).
A timestamp in seconds like 1700000000 has 10 digits (for current dates); in
milliseconds, 1700000000000, it has 13. When converting a timestamp to a date, choose
the correct granularity — interpreting milliseconds as seconds would push the date thousands of
years into the future. This tool lets you choose it in both directions.
The timestamp itself is always absolute (referenced to UTC). The time zone only matters when displaying or interpreting a readable date. When converting a date to a timestamp, you indicate whether the fields you typed are in your local time or in UTC. When converting a timestamp to a date, the tool shows the result in both your local time and UTC, as well as in ISO 8601.
Systems that store the Unix timestamp in a signed 32-bit integer overflow on January 19, 2038. Modern languages (including JavaScript, which uses 64-bit floating point) don't have this problem for common dates.
Because local time depends on the time zone configured on the device. The same timestamp shows different hours in São Paulo and in Lisbon, but the UTC value and the ISO 8601 value are the same everywhere.
From your device's clock. It fills the readable date with the current local time and the timestamp field with the corresponding epoch, respecting the selected granularity.