Book the call for the right hour
Working with a client in another country means doing time zone maths every week, and it is easy to be an hour out. Daylight saving starts and ends on different dates in different places, a few regions are offset by half or three quarters of an hour, and some do not change their clocks at all.
This time zone converter takes a date and a time in one place and shows the time in another. It uses the time zone rules built into your own browser, so it knows about daylight saving on the exact date you pick, and nothing is sent anywhere.
How to convert a time
- Pick the date. It matters, because daylight saving changes the gap between places.
- Enter the time where you are, or where the meeting is being set.
- Choose the From and To places. My time zone uses the setting on your device.
- Read the time in the other place, which day it falls on, the difference in hours, and both UTC offsets.
How the conversion works
time there = time here − UTC offset here + UTC offset thereEvery time zone is described by its offset from UTC, the world reference time. New York in winter is UTC−5; London in winter is UTC+0. Take the offset away to get UTC, add the other place's offset to get the local time there.
The calculator looks up both offsets for the date you chose. If you pick a time that is skipped when clocks go forward, it moves to the next real time and says so. If you pick a time that happens twice when clocks go back, it uses the first one.
Worked example: 9:00 in New York to London
A designer in New York wants to call a client in London at 9:00 on Tuesday 10 November 2026.
- New York on that date is UTC−5 (daylight saving ended on 1 November)
- 9:00 in New York is 14:00 in UTC
- London on that date is UTC+0, so it is 14:00 there
London is 5 hours ahead, so the client sees the call at 14:00, 2:00 PM. Try the same time in mid-March and the gap is only 4 hours, because the US moves its clocks forward about three weeks before the UK does.
Daylight saving dates differ
| Region | Clocks go forward | Clocks go back |
|---|---|---|
| United States and Canada | Second Sunday in March | First Sunday in November |
| UK and European Union | Last Sunday in March | Last Sunday in October |
| South-east Australia | First Sunday in October | First Sunday in April |
| New Zealand | Last Sunday in September | First Sunday in April |
| India, China, Japan | No change | No change |
Because the dates differ, the gap between two cities can change several times a year. That is why the converter always asks for a date.
Common time zone slip-ups
- Using a fixed gap all year. New York and London are usually 5 hours apart, but 4 hours for a few weeks in spring and autumn.
- Forgetting half-hour zones. India is UTC+5:30 and Nepal is UTC+5:45, so a whole-hour guess is wrong.
- Getting the day wrong. A Monday morning call from Sydney is still Sunday afternoon in Los Angeles. The converter shows which day it falls on.
- Mixing up abbreviations. Short names like CST mean different things in different countries. City names are clearer, which is why the list uses them.
Frequently asked questions
How do I convert time between time zones?
Find the UTC offset of each place on the date in question, take the first offset away from the time, then add the second. 9:00 in New York at UTC−5 is 14:00 UTC, which is 23:00 in Tokyo at UTC+9. Pick the date, time and places above and the converter does it, daylight saving included.
Does the converter handle daylight saving time?
Yes. It uses the time zone rules in your browser for the exact date you choose, so the offsets are right before and after every clock change. If you pick a time that does not exist because the clocks jump forward, it moves to the next real time and explains why in the working.
What is UTC?
UTC, Coordinated Universal Time, is the reference time the world's time zones are measured from. It does not change for daylight saving. Each place is described as UTC plus or minus a number of hours, like UTC+1 for Paris in winter. The converter shows both offsets with every answer.
What is the best time for a meeting across time zones?
Look for the overlap in normal working hours. For New York and London, late morning in New York is afternoon in London, which suits both. For far-apart places such as Los Angeles and Singapore, one side usually takes an early or late slot. Try a few times here to find the least awkward option.
Related calculators
More free tools from CloveDesk
CloveDesk gives freelancers and small teams one place for quotes, e-signatures, invoices, files and a portal for each client.
Last updated: