ConverterHub

Time Zone Difference (World Clock)

What is the time difference between two cities?

How it is calculated

The tool takes two cities from a fixed list, each tied to an IANA time zone such as Europe/London or America/New_York. It reads each zone's UTC offset at this moment, including daylight saving time when that zone is currently using it. The current local time of each city is shown as weekday and hour:minute (24-hour). The difference is (offset of A - offset of B) / 3600 in hours, signed: a plus sign means city A is ahead of city B. Half-hour zones appear as .50 and 45-minute zones as .75. Because the offsets are for now, the same pair can show a different gap on another date when only one city has changed its clock.

Worked example

On 16 October 2026, A is London and B is New York. Both are on summer time on that date: London on British Summer Time, UTC+1, and New York on Eastern Daylight Time, UTC-4. Difference = (+1) - (-4) = 5 hours, shown as +5.00 h, so London is 5 hours ahead. The local times shown are the real current times in both cities. After 25 October London returns to UTC+0 while New York keeps summer time until 1 November, so the gap is 4 hours for a week.

Try this example →

Common mistakes

  • Assuming the gap is always the same. When only one country changes its clocks, the difference shifts by an hour for a few weeks.
  • Reading the sign backwards. A plus means the first city is ahead of the second.
  • Picking a city in the wrong zone, for example a country with several zones, instead of the actual city.
  • Using the shown times to plan a future date. The tool uses the current offsets, not those of the meeting day.

About this calculator

This tool shows the current local time in two chosen cities side by side and the exact time difference between them, correctly accounting for each location's UTC offset and whether either city is currently observing daylight saving time, which is often the part people get wrong when doing this in their head. Because DST start and end dates differ by country, the gap between two cities can actually change by an hour at certain times of year even though neither city's own clock changed.

It is used by remote teams and freelancers scheduling a meeting across time zones, by people planning a call with family or friends abroad, and by travelers figuring out what time it will be at their destination when they land. Anyone who has been burned by joining a video call an hour early or late because of a DST mismatch tends to start double-checking with a tool like this instead of doing the math manually.

Was this helpful?

You can pick up to 3 reactions.

Comments (0)

  • Be the first to comment.

Popular calculators

Loan Calculator

Monthly payment, total interest and full amortization schedule.

Percentage Calculator

Percent change, percent of, and ratio calculations.

Discount Calculator

Calculate final price, savings, and discount amount.

BMI Calculator

Body mass index from height and weight (metric or imperial).

Age Calculator

Compute your exact age in years, months and days from a birth date.

Compound Interest Calculator

Calculate the final amount and interest earned with compounding.

All Calculators