How Time Zone Converter Works
The tool treats the date and time you type as wall-clock time in the "from" zone, then asks the browser's time zone database what UTC offset that zone was actually observing at that exact moment — accounting for daylight saving automatically. From that, it works out the precise instant in time, then reformats that same instant using the "to" zone's rules, offset and all.
How to Use This Tool
- Enter the date and time as it should be read in the "Convert from" zone.
- Pick a "Convert from" zone from the list, or type a custom IANA zone name in the field below it.
- Pick a "Convert to" zone the same way.
- Select Convert Time to see the equivalent date and time in the destination zone.
Example
2:00 PM on 15 June 2026 in New York (Eastern Daylight Time, UTC−4 in June) converts to 3:00 AM on 16 June 2026 in Tokyo (Japan Standard Time, UTC+9, which doesn't observe daylight saving).
Helpful Tips
- If a custom zone field is filled in, it takes priority over the dropdown selection for that side.
- Because the conversion is offset-aware, it automatically gets daylight saving transitions right, even in zones where DST starts or ends on unusual dates.
- The result also shows the current offset difference between the two zones, which is handy for scheduling calls across regions.
Frequently Asked Questions
Does this tool account for daylight saving time?
Yes. It reads the actual offset your browser's time zone database reports for that specific date, so DST transitions are applied correctly rather than assumed.
Can I use a custom time zone that isn't in the list?
Yes — type any IANA time zone name, like "Asia/Kolkata" or "America/Denver", into either custom zone field and it will be validated automatically.
What happens if I enter an invalid time zone name?
The tool checks it against your browser's time zone database and shows a friendly error if the name isn't recognized.
Is the offset difference shown always the same for a given pair of zones?
Not necessarily — it can change across the year for zones that observe daylight saving time, which is why it's calculated for the exact date you entered.
This tool runs entirely in your browser. Your input is not uploaded to any server.