Time Zone Converter
Compare a time across cities and find a slot that works for everyone.
About the time zone converter
Every city gets a row, and every column is the same instant. Hover or tap any hour and the whole column lights up, so you can read one moment across every city at once instead of converting them one pair at a time. Tap again to pin a time while you write it down.
The hours are colour-coded by what they mean locally โ working hours, early morning, evening, and the middle of the night โ so a slot that suits everyone is something you spot rather than something you calculate. A marker shows where the local date rolls over, which is the detail that causes most cross-timezone scheduling mistakes.
Your chosen cities and reference zone are remembered between visits, and daylight saving is applied from your browser's own IANA time zone database. That last detail matters: a converter built on a hard-coded offset table silently goes wrong twice a year, and gets the transition weeks wrong for the southern hemisphere permanently.
Why time zones are harder than they look
Offsets are not fixed properties of a place. They change with daylight saving, on dates that differ by country and sometimes by region within a country. The US and Europe switch on different weekends, so for a few weeks each spring and autumn the gap between London and New York is four hours rather than the usual five โ which is exactly when recurring meetings quietly break.
Not every offset is a whole hour, either. India runs at UTC+05:30, Nepal at UTC+05:45, and parts of Australia at UTC+09:30. And some places have abolished the switch entirely while their neighbours kept it. This is why time zones are always looked up rather than calculated.
Picking a time that works
- US East and Western Europe โ the reliable overlap is roughly 13:00 to 17:00 UK time.
- Europe and India โ comfortable from about 13:00 to 18:00 in India.
- Europe and East Asia โ early European morning, around 08:00โ10:00 UK, is late afternoon in Singapore and Tokyo.
- US West and East Asia โ genuinely difficult. Someone takes an early morning or a late evening; alternating who does it is the fair approach.
Frequently asked questions
How do I find a meeting time that works across time zones?
Add every participant's city, then run your cursor along the grid until you find a column where every cell is in the working-hours colour. Each column is the same instant, so a column that looks good for everyone is a slot that works for everyone.
Does this handle daylight saving time?
Yes, automatically. Conversions come from your browser's IANA time zone database, so each location uses the rules that actually apply on the date you have chosen โ including the weeks when regions are out of step with each other.
What is the difference between UTC and GMT?
In everyday use they are interchangeable. UTC is the modern atomic-clock standard and the one to use in technical contexts; GMT is a time zone that observes British Summer Time, so the UK is UTC+1 in summer despite GMT meaning UTC+0.
Why is the difference between two cities not always the same?
Because countries start and end daylight saving on different dates. London and New York are usually five hours apart, but for a couple of weeks each year they are four, which is a common cause of missed calls.
Are my selected cities saved?
Yes, in your browser's local storage on this device. Nothing is sent to a server, and clearing your browser data removes them.