Convert Unix Seconds, Milliseconds and Time Zones
Resolve timestamp unit and time-zone mismatches before using a converted date in logs or an API request.
Use the interactive tool ↓Identify the timestamp unit
Unix time is commonly expressed as seconds since the start of 1 January 1970 UTC; many JavaScript APIs instead use milliseconds. The same number interpreted in the wrong unit can produce a date decades away from the intended event.
Unix Timestamp Converter
Current Unix time
1792918404
Timestamp → Date
Date → Timestamp
Start with the epoch as a test
Enter timestamp 0 with Seconds selected. The UTC result should represent 1 January 1970 at 00:00:00. The local-time result may show a different date or hour because it applies the browser’s time zone.
For a later fixed test, 1700000000 seconds represents 2023-11-14T22:13:20Z. Switching to milliseconds requires 1700000000000 to describe that same instant. The unit selector does not multiply the input automatically; it changes how the existing input is interpreted.
Read UTC and local time as the same instant
The converter displays local time, UTC and an ISO representation. These are different representations of one instant, not competing clocks. The ISO result’s Z means UTC. When comparing logs from several systems, preserve the offset or use a common UTC representation.
- Confirm the source system’s seconds/milliseconds convention.
- Select that unit and paste the timestamp.
- Compare UTC with the expected event.
- Include the unit with any copied number.
Convert a local date deliberately
The date-and-time input is labeled local. It interprets the selected wall-clock date/time in the browser’s time zone; it has no independent zone selector. Two people entering the same local clock time in different zones can therefore produce different Unix timestamps.
Daylight-saving transitions can make a local time ambiguous or unavailable. Use an explicit offset in the source system when exact scheduling matters, and verify the resulting UTC instant. This date picker is not a time-zone database exploration tool.
Troubleshoot invalid or shifting values
Check the selected unit, copied digits and supported date range first. The current-time display updates every second, so use a fixed input for reproducible checks. For whole calendar dates, birthdays or inclusive date ranges, use Date Difference Calculator rather than assuming a calendar day is always an elapsed 24-hour interval in every local zone.