Calculate time differences around the world
Use this tool to calculate time differences between two cities or countries and check the current local time in each place. It is useful for planning international calls, online meetings, travel, live events, and communication with people worldwide.
New York is +5 hours behind London.
How to calculate a time difference?
1. Choose location
Enter your first city or country, or leave London selected as your starting location.
2. Add 2nd location
Search for the city or country you want to compare with your first location.
3. View the difference
The tool shows the current time in both places and the exact difference between them.
Time differences around the world
The table below shows typical time differences from London. The exact difference can change during the year because the UK and other countries may start or end daylight saving time on different dates.
| City | Country | Time & difference |
|---|---|---|
| Dublin | Ireland | 19:38 (0 ur) |
| Lisbon | Portugal | 19:38 (0 ur) |
| Reykjavik | Iceland | 18:38 (−1 ura) |
| New York | United States | 14:38 (−5 ur) |
| Boston | United States | 14:38 (−6 ur) |
| Miami | United States | 14:38 (−6 ur) |
| Toronto | Canada | 14:38 (−6 ur) |
| Chicago | United States | 13:38 (−7 ur) |
| Dallas | United States | 13:38 (−7 ur) |
| Denver | United States | 12:38 (−8 ur) |
| Phoenix | United States | 11:38 (−9 ur) |
| Los Angeles | United States | 11:38 (−9 ur) |
| Vancouver | Canada | 11:38 (−9 ur) |
| Mexico City | Mexico | 12:38 (−8 ur) |
| Rio de Janeiro | Brazil | 15:38 (−5 ur) |
| City | Country | Time & difference |
|---|---|---|
| Buenos Aires | Argentina | 15:38 (−5 ur) |
| Cape Town | South Africa | 20:38 (0 ur) |
| Cairo | Egypt | 21:38 (+1 ura) |
| Istanbul | Turkey | 21:38 (+1 ura) |
| Dubai | U. A. E. | 22:38 (+2 uri) |
| Doha | Qatar | 21:38 (+1 ura) |
| Islamabad | Pakistan | 23:38 (+3 ur) |
| New Delhi | India | 00:08 (+3 ur 30 min) |
| Bangkok | Thailand | 01:38 (+5 ur) |
| Singapore | Singapore | 02:38 (+6 ur) |
| Beijing | China | 02:38 (+6 ur) |
| Tokyo | Japan | 03:38 (+7 ur) |
| Seoul | South Korea | 03:38 (+7 ur) |
| Sydney | Australia | 04:38 (+8 ur) |
| Auckland | New Zealand | 06:38 (+10 ur) |
These are general comparisons rather than fixed year-round differences. Use the live tool when you need the correct time for a particular date.
What are time zones?
Time zones allow different parts of the world to use local clock times based broadly on their position around the Earth. Because the Earth rotates, sunrise, midday, and sunset happen at different times in different locations.
Modern time zones are measured in relation to UTC, the international reference time standard. Locations may be ahead of or behind UTC by a whole number of hours, but some use offsets of 30 or 45 minutes.
Time zone borders do not always follow straight geographical lines. Governments choose official time zones, so neighbouring regions may use different local times, while a very large country may use one national time across its entire territory.
Useful facts about world time differences
- There are more local time offsets than the 24 whole-hour divisions suggested by the hours in a day.
- Some locations use half-hour differences rather than complete hours.
- Nepal uses an offset of UTC+5:45.
- India uses UTC+5:30 throughout the country.
- China uses one official time across the whole country despite its large geographical size.
- Some countries and regions change their clocks seasonally, while others do not.
- The difference between London and Sydney is commonly between 9 and 11 hours, depending on the time of year.
- Locations on opposite sides of the International Date Line may have different calendar dates even when their clock times look similar.
- Accurate time comparisons are important for international travel, transport, online events, business, and communication.
How to calculate time differences manually
To calculate a time difference manually, compare the UTC offsets of both places. If London is using GMT at UTC+0 and Dubai is at UTC+4, Dubai is four hours ahead.
During British Summer Time, London moves to UTC+1. Dubai stays at UTC+4, so the difference becomes three hours.
You must also consider whether either place observes daylight saving time and when its clock changes take place. Because these rules vary, the easiest and most reliable option is to use a live tool that applies the correct time zone information automatically.
World time zone map
A world time zone map can help you understand how local times are distributed across countries and continents. It shows the official boundaries of time zones and explains why two places at similar longitudes may still use different clock times.
