katlab tools/timestamp

Unix Timestamp · Converter

Convert epoch timestamps to human dates and back — seconds or milliseconds, any time zone, all in your browser.

Everything is processed locally. Nothing is uploaded to a server.
Current epoch

Timestamp → Date

Date → Timestamp

How to convert a Unix timestamp (free)

Paste an epoch number into Timestamp → Date to see it as a readable date in your local time zone, UTC and ISO 8601. Type or paste a date into Date → Timestamp to get the epoch value in seconds and milliseconds. Everything runs locally — nothing is uploaded.

What is Unix / epoch time?

Unix time counts the seconds since 1 January 1970, 00:00:00 UTC (the "Unix epoch"), ignoring leap seconds. Because it is a single number in UTC, it is unambiguous across time zones, which is why databases, logs and APIs use it everywhere.

Seconds vs milliseconds

Traditional Unix time is measured in seconds. JavaScript's Date.now() and many modern systems use milliseconds. A rough guide by digit count:

10 digitsseconds (e.g. 1700000000)
13 digitsmilliseconds (e.g. 1700000000000)

This tool auto-detects the unit from the magnitude, and you can override it with the Seconds / Millis toggle.

Is my data private?

Yes. All parsing and formatting happen in your browser tab. Nothing you enter is sent to a server, and the converter keeps working offline once the page has loaded.