Epoch milliseconds to Date Converter – Free, Online, Private
Convert a Unix timestamp in milliseconds, the unit JavaScript Date uses, into a UTC instant and a local time.
How to convert Epoch milliseconds to Date
- Paste a 13-digit millisecond count, or any number of milliseconds since the epoch.
- Read the ISO time and the local time.
- Divide by 1000 yourself only if a library wants seconds. The output already prints both.
Why a separate page
JavaScript, Java, and many JSON APIs store time as milliseconds. A 13-digit number fed to a seconds converter lands centuries in the future. This page multiplies nothing. The number is the Date argument. 1700000000000 milliseconds is the same instant as 1700000000 seconds. The output prints UTC, local time, the seconds form and the milliseconds form so you can confirm the unit. Sub-millisecond values cannot be represented and are not rounded into existence.
Range
Date covers roughly 100 million days on either side of the epoch and then returns an invalid date, which this page reports as an error. A timestamp in microseconds, 16 digits, is outside the useful range and should be divided by 1000 before you paste it. Negative milliseconds are before 1970. The local line depends on the browser zone, the same caveat as the seconds page.
Worked example
1700000000000 is 2023-11-14T22:13:20.000Z, matching the seconds sample with three extra zeros. If your log prints 1700000000000.0, the trailing decimal is still a finite number and parses. If the log wraps the number in quotes inside a sentence, paste only the digits. Pair the result with the date to Unix page when you need to edit the civil time and convert back.
Logs
Millisecond timestamps show up in browser performance marks, Java Instant.toEpochMilli, and many document databases. Converting one while reading a log should not require sending the log line anywhere. The page only needs the number.
Frequently asked questions
How many digits?
Current times are 13 digits. Ten digits are seconds and belong on the other timestamp page.
Does it match Date.now()?
Yes. Date.now() returns this unit, and new Date(milliseconds) is what the page formats.
What if the date is Invalid?
The number is out of range or not numeric. The page shows an error instead of a bogus year.
Is the value uploaded?
No.