Convert timestamp
Paste a timestamp or a date. We work out on our own whether it is seconds, milliseconds or microseconds — and tell you which we used, instead of guessing silently.
Your text stays on your device: nothing is uploaded
Result
Paste something on the left: the result appears as you type.
How it works
A timestamp counts the time since 1 January 1970. The catch is the unit: the standard says seconds, JavaScript uses milliseconds, some databases microseconds, and the number alone does not say which. Get it wrong by a thousand and you land in 1970 or in the year 55000. Here the unit is inferred from the magnitude and, above all, we tell you which one we picked, so if it is wrong you see it at once. It works the other way round too.
Frequently asked questions
- How does it choose between seconds, milliseconds and microseconds?
- By the number of digits: up to 11 means seconds, 12 to 14 milliseconds, 15 or more microseconds. So a millisecond timestamp from before 3 March 1973, including dates before 1970, is read as seconds: the “Read as…” line tells you, and dividing it by a thousand fixes it.
- What if my number is in nanoseconds?
- Nanoseconds are not recognised: a 19-digit number is read as microseconds and gives a date tens of thousands of years ahead. Remove the last three digits and paste it again: it becomes microseconds, and you get the same instant, to the millisecond.
- How is a date without a time zone read?
- It depends on the form. “2018-01-18T01:30:22”, with a time but no Z or offset, is taken as your device’s local time; “2018-01-18”, a date alone, is taken as midnight UTC. To be sure, add Z or an offset such as “+02:00”. Only year-month-day dates are read, plus the form of the “UTC time” line: “18/01/2018” or “18 January 2018” are not guessed, because every browser would read them its own way. A date that does not exist, such as 30 February, is reported.
- Does local time account for daylight saving?
- Yes: it uses the time zone set on your device, with the summer or winter offset in force on that date, not today. In London, an August timestamp comes out one hour ahead of UTC even if you convert it in December. For any other zone, work from the UTC line.
- Does it work with dates after 2038?
- Yes. 19 January 2038 at 03:14:07 UTC, timestamp 2147483647, is the limit for systems that count seconds in 32 bits; there is no such limit here. If a program of yours shows December 1901 where you expected 2038 or later, it is storing time in 32 bits.
What you paste is never uploaded. Anywhere.
The text you type stays in your browser’s memory: no request goes out while you type. You can paste something confidential.
- Processed locallyEverything happens on this page.
- Nothing to upload, nothing to wait forNothing to upload, no waiting.
- Nothing to deleteWe keep nothing: nothing reaches us.