Pick a source time and city, then add every other city you care about. The converter shows the matching local time in each one and updates the moment you change anything. It reads the offsets from your browser's IANA time zone database, so daylight saving shifts are baked in — you never enter "+5" or "-8" by hand.
How time zones actually work
Every zone is described as an offset from UTC (Coordinated Universal Time), the world's reference clock. A few offsets surprise people:
- Whole-hour offsets are not universal. India runs on UTC+5:30, Nepal on UTC+5:45, and parts of Australia on UTC+9:30. A "half-hour" time zone is real, not a typo.
- One country can span many zones. The continental US covers four (Eastern, Central, Mountain, Pacific); Russia stretches across eleven.
- China uses a single zone (UTC+8) despite being as wide as the US — so the sun rises hours "late" in the far west.
- UTC never changes. That is why servers, flight schedules, and coordinated deadlines are almost always written in UTC.
The daylight saving trap
DST is where scheduling quietly breaks. The dates don't line up between regions:
- The US springs forward the second Sunday of March and falls back the first Sunday of November.
- The EU and UK switch on the last Sunday of March and the last Sunday of October.
- For about two weeks each spring and autumn, New York and London are 4 hours apart instead of the usual 5. A recurring 3pm London call lands at a different New York time during those windows.
- Much of the southern hemisphere (Australia, parts of South America) does DST in reverse, shifting in their spring — which is the northern autumn.
Plenty of places skip DST entirely: Arizona (except the Navajo Nation), Hawaii, most of Asia, the Middle East, and Africa. That is a feature, not a rounding error.
Book the meeting, not just the time
When you settle on a recurring slot, sanity-check it around the DST changeover dates above. A "9am every Monday" call agreed in January can silently drift by an hour in March for one side. The safest habit for one-off international deadlines: state the time in UTC and let each person convert once.
Getting a meeting to work for everyone
For a genuinely global team there is often no time that suits all zones — someone eats the early morning or late night. A rough overlap map helps:
- US East Coast & Western Europe: 8am–11am New York (1pm–4pm London) is the reliable overlap.
- Europe & India: afternoon in Europe works; India is 3.5–4.5 hours ahead of the UK.
- US & East Asia: brutal. Early morning one side is late evening the other — rotate who suffers.
FAQ
Does the converter handle daylight saving time automatically?
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Yes. It uses your browser's IANA time zone database, so each city's offset shifts on the exact date that region starts or ends DST. You never set an offset by hand.
Why is the gap between two cities sometimes different than usual?
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Because regions change their clocks on different dates. For roughly two weeks each spring, New York sits 4 hours behind London instead of the usual 5, because the US switches before the EU. The tool tracks the live gap so you don't have to.
What is UTC, and when should I use it?
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UTC is the global reference clock that ignores DST. Every zone is an offset from it — Tokyo is UTC+9, India UTC+5:30, New York UTC-5 in winter. Use UTC for logs, server timestamps, and one-off international deadlines where a mistaken hour is costly.
Is the converter free and private?
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Yes on both counts. It is 100% free with no signup, and every calculation happens in your browser. No times, cities, or meeting details are uploaded, logged, or shared.
Do I need to install anything?
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No. It runs in any modern browser on desktop or mobile — nothing to download, sign up for, or configure.