Time Zone Calculator guide
Time Zone Calculator: Convert Times Around the World
Use our time zone calculator to convert a time from one city or time zone to another, allowing for daylight saving time.
By the AllCalculator editorial teamUpdated 16 October 20261 min read
Setting up a call with family abroad or a meeting with colleagues overseas? Our Time Zone Calculator converts a time between any two of more than 30 major cities.
How to use the calculator (Time Zone Calculator)
- Choose the place you're converting from.
- Choose the date and time there.
- Choose the place you're converting to.
You'll see the time there, the time difference and the same moment in cities around the world.
Daylight saving time
Many countries move their clocks in summer, but not on the same dates. The calculator uses the rules for the date you choose, so the difference is always right.
- The UK uses GMT (UTC+0) in winter and BST (UTC+1) from the last Sunday in March to the last Sunday in October.
- The US changes its clocks on different dates, so for a few weeks a year the gap between London and New York is 4 hours instead of 5.
- Many countries, such as India, China and Japan, don't change their clocks at all.
Worked examples
- With the calculator's default settings, 9:00 in London is 4:00 in New York, which is 5 hours behind.
- In July, 9:00 in London is 13:30 in India, which is 4 hours 30 minutes ahead.
Frequently asked questions
What's UTC?
Coordinated Universal Time, the world's time standard. It's the same as GMT for everyday purposes.
Why do some places have half-hour offsets?
Countries choose their own time zones. India is UTC+5:30 and Nepal is UTC+5:45.
How do I deal with jet lag?
See our Jet Lag Calculator for tips on adjusting.
Sources and further reading
Links open official and independent websites in a new tab.
This guide is general information to help you understand your options. It isn't financial, tax, legal or building advice and doesn't take your personal circumstances into account. Figures were checked when the guide was last updated and can change, so confirm anything important with GOV.UK, HMRC, a regulated adviser or a qualified tradesperson.