How to Read and Convert Unix Timestamps
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A Unix timestamp represents elapsed time from 1 January 1970 UTC. It is often used in logs, APIs and databases because it is a single number, but the number alone does not tell you whether the unit is seconds or milliseconds.
Steps
- Open Timestamp Converter and choose timestamp-to-date or date-to-timestamp.
- If entering a timestamp, check whether it is in seconds or milliseconds.
- Review both the UTC value and local display time.
- Copy the converted value and keep the chosen time zone with your notes.
Seconds versus milliseconds
A ten-digit value is commonly seconds; a thirteen-digit value is commonly milliseconds, but digit count is only a clue. Confirm the format from the API or log that produced the number.
If milliseconds are read as seconds, the resulting date may be far in the future. If seconds are read as milliseconds, it may land near January 1970.
UTC and local time
The timestamp itself refers to a UTC instant. A local date and time can differ by the device's time zone and daylight-saving rules. When comparing systems, share the ISO UTC date or include the time zone explicitly.
Date Converter is useful for common date representations; Timestamp Converter lets you select seconds or milliseconds and view UTC alongside your local time.
Common questions
Does a Unix timestamp include a time zone?
It represents a UTC instant. Time zones affect how that instant is displayed as a local clock time.
Why does my timestamp show a different hour?
The converter may be showing local time while the source was recorded in UTC or another time zone.