Unix timestamp converter — seconds and milliseconds
Convert Unix epoch seconds or milliseconds to ISO UTC and back. Explicit units, negative timestamps and millisecond precision.
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How it works
Unix time starts at 1970-01-01T00:00:00Z and does not count leap seconds. Choose seconds or milliseconds explicitly. Date input must be ISO UTC ending in Z.
Example
1704067200 seconds is 2024-01-01T00:00:00.000Z. The same instant is 1704067200000 milliseconds.
Why are my results in 1970?
You may have mixed seconds and milliseconds. This tool never guesses from the digit count. It accepts dates from 1900 through 2100 and displays both units in the result.