Convert dates and Unix timestamps

For developers and analysts matching technical logs to human dates, Unix Timestamp handles conversions in either direction.

Translate a calendar date into a Unix timestamp, or turn a timestamp back into a date you can verify. No upload or storage is involved.

How to use

Paste an ISO date or a numeric timestamp into the input area.
Choose the conversion you need: seconds to ISO, ISO to seconds, milliseconds or RFC 2822.
Run the conversion to display the matching value in the result area.
Check that the selected unit matches your original data, then copy the result.
Clear the fields before converting another value so results stay separate.

Example

The provided example contains an ISO date. After converting, look at the numeric value and the unit shown. If you test the reverse direction, check that the rebuilt date represents the same instant rather than a different local time.

Input

2026-08-13T12:00:00Z

Output

1786622400

Limits and formats

Seconds and milliseconds must not be confused, so pick the conversion that matches your data.
A date without time zone information may be interpreted differently depending on context.
The tool does not replace a date library for complex calculations or special calendars.
Supported text files can be imported, but review the values before reusing them.

Where processing happens

Everything runs in your browser. The date or timestamp you enter stays on your device and is not sent anywhere. You can convert technical values without creating an account.

Frequently asked questions

How can I tell whether my timestamp is in seconds or milliseconds?

A millisecond timestamp is much longer than a seconds value. If the converted result produces a very distant date, switch the unit and run the conversion again.

Can I convert a date with a time zone?

Use an ISO notation that includes the offset or the final Z. Without that detail, the date may be treated as local time and give a different result.

Is the result ready for a database?

It can work as a reference value, but check the format your database or application expects. Some use seconds, while others use milliseconds.