Date & Time Converter
Move between a calendar date and Unix time without relying on an implicit timestamp unit or an unexplained time zone.
A QUICK WALKTHROUGH
How to use this tool
- Choose whether you are starting with a date and time or a Unix timestamp.
- Select the input time zone or timestamp unit, then enter the value.
- Convert and copy the Unix, ISO 8601, local, and UTC representations you need.
Time zone and unit are explicit
A date-time input can be interpreted in your browser’s local time zone or as UTC. A timestamp input must be marked as seconds or milliseconds. The result identifies the detected browser time zone and also includes an ISO 8601 UTC value.
Local clock changes need care
Browser-local conversion follows the time-zone rules available on your device. A local clock time skipped by a daylight-saving transition is rejected. A repeated clock time can still be ambiguous because a date-time field does not include an offset; use UTC or a timestamp when the exact instant matters.
GOOD TO KNOW
Common questions
Are Unix timestamps tied to a time zone?
No. A Unix timestamp identifies an instant relative to the Unix epoch. Time zones only change how that instant is displayed.
Does the tool guess seconds or milliseconds?
No. You select the unit explicitly, avoiding errors caused by digit-count guessing.
Does conversion use a server?
No. It uses the browser Date and Intl APIs on this device.