Epoch timestamp converter
ConvertExperimentalLimited support. Verify anything critical.
An epoch timestamp converter translates between a human-readable date-time and the number of seconds or milliseconds since 1970-01-01 at 00:00:00 UTC. The tool accepts either common timestamp precision automatically, displays an ISO UTC value, and also shows the browser's local rendering when converting back. Date parsing and arithmetic use the device's JavaScript time implementation and never send the chosen moment or time zone to a server.
Skip to the toolThis tool processes the values or files you choose on your device. They are not uploaded.
Output
Limits
- Dates are limited to the range supported by the browser Date implementation.
Warnings
- A datetime-local input has no named time zone and uses the browser's current local zone.
How to use Epoch timestamp converter
Seconds versus milliseconds
Unix tools often disagree on precision. This result shows both values so API payloads can be checked without relying on digit counting alone.
Local time caveat
The date picker represents the browser’s current zone. Use the separate time-zone converter when a named IANA location and daylight-saving rules matter.
How it works
- Enter what you haveType or pick your local date and time, Unix timestamp. Nothing is submitted anywhere.
- It runs in this tabThe calculation happens on your device, using your browser's own data.
- Take the resultRead the seconds, milliseconds, ISO date, local date, then copy, download, or share a link.
Implements Unix epoch arithmetic with the browser Date and Intl APIs.
- Basis
- spec-only
- Licence
- MIT
- Last reviewed
Frequently asked questions
How does the tool distinguish seconds from milliseconds?
Numeric magnitudes below one hundred billion are treated as seconds; larger values are treated as milliseconds.