Time Zone Converter

Enter a time and choose two cities to see what time it is on the other side.

Results

Please enter valid values.

Arranging a call abroad or phoning family overseas always raises the same question: what time is it there? The gap is not even constant — Europe and North America change their clocks twice a year, on different dates.

The converter applies daylight saving time automatically for the date you choose, so you do not have to remember whether London is currently on GMT or BST, or New York on EST or EDT.

How to calculate Time zone

  1. Enter the date and time.
  2. Choose the city that time applies to.
  3. Choose the city to convert to and read the local time, date and difference.

Time zone formula

  • Target time = source time − source UTC offset + target UTC offset
  • Time difference = target UTC offset − source UTC offset

Time zone example

On 4 October 2026, 15:00 in London (UTC+1, British Summer Time) is 10:00 in New York (UTC−4): a difference of five hours.

Time zone: common questions

Are UTC and GMT the same?

In everyday use, yes. UTC is the official standard based on atomic clocks; GMT is winter time at Greenwich in London. They show the same time.

Why does the date change?

With a large time difference the other city may already be on the next day, or still on the previous one. The date line and the note under the results say so.

Does every country use daylight saving time?

No. Most of Asia and Africa do not, and Türkiye has stayed on UTC+3 all year since 2016. The converter knows the rule for each city in the list.