Runs locally in your browser
Time Zone Converter
Convert a local date and time between IANA zones. Daylight-saving rules, UTC output, offsets, and Unix time are calculated automatically.
2026-09-01, 21:00:00 GMT+8
Asia/Shanghai
2026-09-01, 09:00:00 GMT-4
2026-09-01T13:00:00.000Z
1788267600
+480 minutes
✓ Converted locally with IANA time zone rules
Convert local clock time between regions
Choose the zone in which the entered clock time occurs, then choose the destination zone. The converter resolves one instant and displays it using the destination’s offset rules for that date.
IANA zones are better than fixed abbreviations
Names such as America/New_York and Asia/Shanghai identify regions with historical rules. Short abbreviations can be ambiguous, while a fixed numeric offset cannot automatically follow daylight-saving changes.
Frequently asked questions
Does this converter account for daylight saving time?
Yes. It uses the IANA time zone database exposed by Intl, so historical and seasonal offsets are selected for the entered date.
Why can a local time be invalid?
When daylight saving time starts, clocks can skip a range of local times. A value inside that gap does not represent a real instant, so the converter reports an error.
What about an ambiguous time when clocks move backward?
A repeated local clock time can represent two instants. This converter chooses one compatible offset; use an ISO value with an explicit offset when that distinction is important.
Is my date sent to a server?
No. Time zone conversion runs locally through the browser Intl API.