Runs locally in your browser
Unix Timestamp Converter
Convert Unix time in seconds or milliseconds to a calendar date, and the other way around. Conversion runs locally in the browser.
Paste an epoch value from a log or pick a date to get seconds since 1970-01-01 UTC. This converter is for instants, not for age in years.
Date math uses the JavaScript Date object in this tab. Nothing is sent to a time API.
How to use
- Choose seconds or milliseconds.
- Enter a timestamp or a date.
- Read the matching date or epoch value.
How it works
Unix time counts seconds, or sometimes milliseconds, from the UTC epoch. Ten-digit values are usually seconds. Thirteen digits are usually milliseconds.
The page can show local and UTC readings from the same instant. Invalid numbers or dates return an error instead of a guessed clock.
Examples
Log line
1710000000 seconds maps to a March 2024 UTC instant you can place beside a server log.
Contract date
A closing date typed as ISO converts to milliseconds for an API that stores epoch millis.
FAQ
Seconds or milliseconds?
Use seconds for classic ten-digit stamps. Use milliseconds for JavaScript Date.now style values.
Does this compute age?
No. Use the age calculator for years, months, and days from a birthday.
What time zone is shown?
You can read UTC and the local zone of this browser. The epoch number itself is timezone-agnostic.
Is conversion offline?
Yes. It uses Date in this tab.
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