Time Zone Converter
Convert a time between world time zones with automatic DST, and plan meetings across cities.
Enter a valid date and time.
🔒 Conversion runs only in your browser — it works offline and nothing is uploaded.
How it works
Pick a source date, time and its zone, then add the cities you care about. Each target zone shows the matching local date and time, its UTC offset and abbreviation, and how many hours it sits ahead of or behind the source. A +1d or -1d marker appears whenever a city lands on a different calendar day.
Accurate across daylight saving
The converter measures each zone's real offset for the exact date you enter using the browser's Intl engine, so daylight saving time is applied correctly. Seoul stays on UTC+9 all year, while New York, London and Paris shift by an hour in summer — no fixed offset is ever assumed, so values stay right around transition days.
Plan meetings in seconds
Set the time to a proposed slot and read off a comfortable hour for everyone at a glance. Use Copy results to grab every city's time at once and paste it straight into an invite or chat. Everything runs in your browser and works offline.
Frequently asked questions
Is daylight saving time handled?
Yes. Each zone's offset is computed for the specific date you enter, so summer and winter time are applied automatically. Zones without DST, like Seoul, never shift, while New York and London move by an hour in summer.
Where do the time zones come from?
The full IANA time-zone list is provided by your browser via Intl.supportedValuesOf. On older browsers that lack it, a curated fallback of major cities (Seoul, New York, London, Tokyo and more) is shown instead.
Is anything uploaded?
No. All conversions run entirely in your browser and work offline, so your meeting times and schedule are never sent to a server.