Convert Unix seconds and millisecond timestamps to readable dates across common timezones. You can also enter a local date and time to get its Unix seconds, milliseconds, and ISO value. Calculations run locally in your browser.
Features
Detects seconds and milliseconds automatically
Shows Unix seconds, milliseconds, and ISO 8601 UTC
Compares local time, UTC, Beijing, Los Angeles, New York, London, and Tokyo
Supports one-click copy for every result
How to use
1Paste a Unix timestamp in seconds or milliseconds.
2Review the converted date-time values in each timezone.
3Edit the date-time field to convert a local time back to a timestamp.
FAQ
What is the difference between seconds and millisecond timestamps?
Unix seconds count whole seconds since 1970-01-01 00:00:00 UTC. Millisecond timestamps count milliseconds from the same moment and are usually 13 digits for current dates.
What is the difference between UTC time and local time?
UTC is the global reference timezone. Local time is calculated from your browser or the selected city timezone, so the same timestamp can display as different clock times.
Why do Los Angeles or New York offsets change on different dates?
Those timezones observe daylight saving time. Their UTC offsets can change during the year, so historical and future dates must be formatted with the date included.
Which timezone is used for the date-time input?
The date-time input is parsed as your browser's local timezone, then converted to Unix seconds, milliseconds, ISO UTC, and the listed city timezones.
Do I need an account to use this tool?
No. Open the page and use it directly; common operations run in your browser.