Input
Output
Formatted result will be displayed here
Unix time counts seconds since the Unix epoch at the start of 1970 in UTC. Converting it to a human date requires splitting the seconds into years, months, days, hours, minutes, and seconds using calendar rules, including leap years and leap seconds handling. This tool does the conversion for both seconds and milliseconds inputs, returns ISO 8601 UTC, and also shows a friendly local form that reflects your current browser timezone.
REST and GraphQL endpoints frequently expose timestamps as Unix seconds. Convert while reading to verify your client is interpreting them correctly.
Some tooling dumps certificate notBefore and notAfter fields as Unix time. Convert to see if a cert is still in its validity window.
stat output on Linux shows modification times in Unix form. Convert to confirm when a file was last written.
When services log in Unix time and UTC ISO, converting makes it obvious whether two events actually happened at the same moment.
By convention Unix time ignores leap seconds, so consecutive real-world seconds may map to the same Unix value during a leap insertion.
Unix time is inherently UTC. The tool derives your local zone from the browser and displays both forms so the offset is explicit.
Divide by 1000 first, or drop the last three digits. The tool supports seconds and milliseconds, not microseconds or nanoseconds.
Your input was too small, likely in seconds when the consumer expects milliseconds, or vice versa. Check magnitude: ten digits is seconds.