Convert Unix seconds or milliseconds to a UTC time, or convert a UTC clock time back to a Unix timestamp.
Unix time counts seconds from 1970-01-01 00:00:00 UTC, ignoring leap seconds. Milliseconds are that count times 1000. A clock time entered here is read as UTC.
Choose seconds or milliseconds before you convert a number. A 10-digit value is usually seconds. A 13-digit value is usually milliseconds. The page does not guess, because guessing turns a seconds value into a date in the far future.
The other direction reads a UTC time such as 2026-01-15T17:00:00Z. There is no time zone on this form. Convert a zoned clock on the time zone page first if the source clock is not UTC.
Pick the direction and the unit.
Paste the number, or a UTC time written with a T between the date and the clock.
Read the UTC result. It is not shifted to your local zone.
2023-11-14T22:13:20.000Z.
Reading a millisecond timestamp as seconds.
Expecting the result to appear in local time.
No. Unix time ignores leap seconds, and so does this conversion.
The number was probably milliseconds, and the form was set to seconds. Switch the unit.