How to use this tool
Enter a Unix timestamp and select seconds or milliseconds to view UTC and browser-local date/time. Or enter a UTC date and time to create Unix seconds and milliseconds.
Quick steps
- Enter a Unix timestamp and specify seconds or milliseconds.
- Review its UTC and local calendar date and time.
- Alternatively enter a UTC date and time to calculate its Unix timestamp.
Practical tip
Unix timestamps represent instants relative to January 1, 1970 UTC. They do not store a time zone. A timestamp in seconds has 1,000 times smaller magnitude than the same instant in milliseconds.
Common questions
Is Unix time always UTC?
Yes. It represents elapsed seconds or milliseconds since the UTC Unix epoch and is independent of display time zones.
How can I tell seconds from milliseconds?
Modern seconds timestamps usually have 10 digits, while milliseconds commonly have 13; choose the explicit unit to avoid ambiguity.
Can I convert dates before 1970?
Yes. Negative timestamps represent instants before the Unix epoch.