Compare the current time in cities around the world, side by side, with UTC offsets and how many hours ahead or behind each one is.
When your work spans time zones, the question is rarely 'what time is it there' in the abstract — it is whether it is a reasonable hour to call someone right now. Seeing several cities side by side answers that faster than arithmetic does.
Add the cities you actually deal with. Each row shows the local time, the date, whether that date is the same as yours, and how many hours ahead or behind it is. The list is ordered east to west, so it reads like a globe.
The most expensive time zone mistakes are date mistakes, not hour mistakes. When it is Tuesday afternoon in London it is already Wednesday morning in Sydney, so 'tomorrow at 9' is genuinely ambiguous between the two. Each row labels the local date as today, tomorrow or yesterday relative to your own, which is the fastest way to catch that class of error.
The east-to-west ordering helps too: cities near the top of the list are ahead of you, cities near the bottom are behind.
Offsets are not fixed. Most of Europe and North America shift by an hour twice a year, on different dates from each other; much of Asia and Africa does not shift at all; the southern hemisphere shifts in the opposite direction from the northern. This means the gap between two cities is not a constant — London and New York are five hours apart for most of the year but four for two short windows, because the two regions change on different weekends.
Every offset here is resolved for the current moment using your browser's own time zone database, so daylight saving is already accounted for. Some zones are not on whole hours either: India is UTC+5:30, Nepal UTC+5:45, and parts of Australia UTC+9:30.
Yes. Offsets are calculated for the current moment from your browser's time zone data, so a city that has just changed clocks shows its new offset without any action from you.
Because it genuinely is a different date there. Each row is labelled today, tomorrow or yesterday relative to your local date, which is the detail most easily missed when scheduling.
The quick-add list covers common business hubs. The full picker below it accepts any IANA time zone your browser supports — several hundred — so you can add the zone containing almost any location.
Yes, in your browser's local storage, so they are still there next time. They do not sync between devices.
A number of zones use 30- or 45-minute offsets — India at UTC+5:30, Nepal at UTC+5:45, Adelaide at UTC+9:30. They are shown exactly rather than rounded.