Compare the time in any two cities — instantly
Live clocks, hour-by-hour conversion tables and the best time to call, for every pair of cities on Earth.
New York City
03:59:31
Sun 2 Aug
London
08:59:31
Sun 2 Aug
London is 5 hours ahead of New York City.
Live day & night · UTC 07:59:31
When can you actually call?
Meeting planner →The overlap between two working days, hour by hour. Change either city in the card above and this redraws.
New York City ↔ London
The working day overlaps from 9:00 AM to 12:00 PM in New York City — 2:00 PM to 5:00 PM in London. Hours shown in New York City time.
Guides & explainers
All guides →Plain-English reading on how time zones actually work — history, daylight saving, jet lag and the world's odder offsets.
Accurate time differences, computed live
Every comparison on this page is worked out from the IANA time zone database at the moment you look at it, so daylight saving time is always accounted for — including the awkward weeks when two cities switch on different dates and their usual gap temporarily grows or shrinks. New York and London are five hours apart most of the year, but briefly four; Sydney and Los Angeles swing between 17 and 19. A static table can't tell you that; a live comparison can.
Beyond the clocks above, each city pair page adds an hour-by-hour conversion table, a best-time-to-call window based on overlapping business hours, the distance and flight-time context for travellers, and the exact dates the difference changes this year. The tools cover meeting planning across several zones, countdowns and date math, and the world clock puts the major cities on a single day/night map alongside current UTC.
If you have ever wondered why time zones exist at all, why UTC and GMT aren't quite the same thing, or why politicians keep arguing about daylight saving, the guides section is written for exactly that kind of curiosity — plain-English explainers, no jargon.