Convert a date and time from one time zone to another, showing the equivalent local time with daylight saving awareness and UTC offsets.
About DST
Daylight Saving Time shifts are handled automatically based on the selected date and IANA timezone rules. Results reflect the offset in effect on that specific date.
Converted time
2026-03-21 · GMT (UTC+00:00)
24-hour format
09:06 EDT → 13:06 GMT
Dates & Time
Convert a date and time between any two IANA time zones instantly, with automatic daylight saving adjustments and UTC offset display.
The calculator uses the Intl.DateTimeFormat API built into modern browsers to perform accurate timezone conversions. It constructs a Date object in the source timezone, then formats it in the target timezone, extracting the converted hours, minutes, date, and UTC offsets. Because it relies on the IANA timezone database, it automatically accounts for daylight saving transitions on the selected date.
DST rules vary by country and change over time. The converter detects whether each timezone is observing standard or daylight time on the selected date and shows the active UTC offset accordingly. The time difference between two zones can change throughout the year as their DST transitions do not always align.
Frequently asked questions
Countries enter and leave daylight saving time on different dates. For example, New York and London are 5 hours apart in winter but only 4 hours apart when the UK has moved to BST but the US has not yet started EDT, or vice versa.
IANA identifiers like America/New_York or Asia/Tokyo are the standard names used by operating systems and programming languages. They encode the full history of UTC offset changes and DST rules for each region.
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