Time Zone Converter
Convert a date and time between major IANA time zones.
Enter your values
Use the fields below, then select Calculate. Your result appears immediately on this page.
How to use the Time Zone Converter
Enter a date and time, choose an IANA source time zone and destination time zone, and convert the moment using browser-supported time-zone rules.
Formula / calculation logic
The source wall-clock time is resolved to an instant, then formatted in the destination IANA time zone.
Worked example
A time entered for Asia/Karachi can be converted to America/New_York with daylight-saving rules applied where supported by the browser.
Important notes
Time-zone law changes over time. This tool relies on the browser’s installed IANA/Intl time-zone data, so very old browsers may have incomplete rules.
Frequently asked questions
Are offsets hard-coded?
No. Named IANA zones are used so daylight-saving rules can be applied.
Why can an offset change during the year?
Some regions observe daylight saving time or have changed time-zone rules historically.