Frequently asked questions
What is Unix time, or the epoch?
It is the number of seconds that have passed since January 1, 1970, 00:00:00 UTC, ignoring leap seconds. It is a simple, timezone-free way to represent a moment.
Seconds or milliseconds, which is my timestamp?
A 10-digit number is usually seconds; a 13-digit number is milliseconds. Open Epoch detects the scale automatically and shows the right date.
Is Open Epoch free?
Yes. Unlimited use, no signup, no login, and no cost.
Are my timestamps sent anywhere?
No. Conversions happen entirely in your browser. Nothing you type is sent to a server.
Can I see a timestamp in another timezone?
Yes. Change the timezone selector, or use the world clock to compare several zones at once.
What is the year 2038 problem?
Systems that store Unix time in a signed 32-bit integer overflow on January 19, 2038. Modern systems use 64-bit time, which pushes that limit far into the future. Open Epoch handles dates well beyond 2038.
Does it work offline and on mobile?
The page is lightweight and responsive. Once loaded, the conversions run locally in your browser.
Why does it remember my settings?
Your timezone, theme, and language are saved in your browser's local storage so the tool feels right next time. Nothing leaves your device.
Still curious? Read the about page.