Date & TimeLOCALRuns in your browser
Unix Timestamp Converter
Convert Unix seconds, Unix milliseconds, and ISO 8601 timestamps with UTC, local time, relative time, and calendar breakdown.
This tool handles input and primary processing in your browser and is designed not to send the input to QuickKit’s server.
Converted time
| Unix seconds | — |
|---|---|
| Unix milliseconds | — |
| ISO 8601 (UTC) | — |
| UTC | — |
| Local time | — |
| Relative | — |
| Weekday | — |
| ISO week | — |
| Day of year | — |
| Quarter | — |
How it works
Auto-detect reads a bare number as seconds, or as milliseconds once it is large enough (about 13+ digits). ISO 8601 input must include Z or an explicit offset. Local time uses your browser's current timezone; UTC, ISO week, and day-of-year are stable across devices. Relative time is measured from the moment you run the conversion.