How to use the time difference calculator
- Pick the first location: a city from the list, or Your time zone.
- Pick the second location in the same way.
- Read the result: how many hours and minutes one place is ahead of or behind the other.
Under the result, both places show their live clocks, so you can see the current time and date in each. The calculator also looks up to 12 months ahead and shows the next date the difference changes because one of the places starts or ends daylight saving time. If neither place changes its clocks, the difference stays the same.
The 24-hour table lists every hour of the day side by side, which makes it easy to see that 9:00 in one city is, for example, 17:00 in the other. The Swap button switches the two locations, so you can read the table from the other side.
How time differences work
Every place keeps time at an offset from Coordinated Universal Time (UTC). The time difference between two places is simply the difference between their offsets. Paris in winter is UTC+1 and New York is UTC−5, so Paris is six hours ahead.
Not all offsets are whole hours:
| Place | Offset | Note |
|---|---|---|
| Newfoundland, Canada | UTC−3:30 | Half-hour zone, with summer time |
| India | UTC+5:30 | Half-hour zone, no summer time |
| Nepal | UTC+5:45 | 45-minute zone |
| Adelaide, Australia | UTC+9:30 | Half-hour zone, with summer time |
| Chatham Islands, New Zealand | UTC+12:45 | 45-minute zone, with summer time |
Why the difference changes during the year
Daylight saving time moves clocks forward by an hour in summer, but countries do not all change on the same day, and many do not change at all.
- Europe and North America. The European Union and the United Kingdom change on the last Sunday of March and of October. The United States and most of Canada change on the second Sunday of March and the first Sunday of November. For two or three weeks in March, and about a week in late October or early November, the gap across the Atlantic is one hour smaller than usual.
- Northern and southern hemispheres. Australia and New Zealand have summer time from about October to April, the opposite of Europe. The gap between them and Europe changes twice in spring and twice in autumn.
- Places without summer time. Japan, India, China and many tropical countries keep the same offset all year, so their difference from Europe or North America changes by one hour whenever the other place changes.
This is why the calculator shows the next change date. For background, see daylight saving time. To compare more than two places for a call, use the meeting planner, or follow many cities live on the world clock.