Which country has the most time zones?

France, counting its overseas territories — twelve. Among contiguous countries Russia has the most, at eleven, followed by the United States and Canada at six each. China is the notable outlier in the other direction: it spans five geographic zones but runs the whole country on one, Asia/Shanghai.

Why does this site list more IANA zones for a country than the number of time zones it is usually said to have?

Because the IANA database splits a zone whenever any part of it has had a different history of clock changes, not only a different offset today. The United States is usually described as having six zones, but IANA carries entries such as America/Indiana/Indianapolis and America/North_Dakota/Center because those places switched zone or daylight-saving rule at some point. They agree with their neighbours on the current offset and differ only on past dates.

Do all countries observe daylight saving time?

No — most do not. Daylight saving is largely a European and North American practice, along with parts of Australasia and a handful of countries elsewhere. Almost all of Africa and Asia keep a fixed offset year-round, and several countries have abolished it in recent years. Each country page states which of its zones observe it and when the next change falls.

Why does the difference between two countries change during the year?

Because the two ends move on different dates, or only one moves at all. London and New York are five hours apart for most of the year but four for a couple of weeks each March, when the United States has already changed its clocks and Europe has not. Between hemispheres the swing is two hours, because the two sides move in opposite directions.

World clocks & live time

Time zones, country by country

All 244 countries and territories, each with every IANA time zone it uses, the current UTC offset of each, and whether it observes daylight saving. 24 of them span more than one zone, which is why a single national time is often the wrong answer.

Every country page also lists its cities, linking through to a live clock for each — 34,043 in total. Looking for one place rather than a country? Start from the city index.

Every country and territory

Ordered by the size of each country's largest city, so the places most people are looking for come first.

Questions & answers

Which country has the most time zones?: France, counting its overseas territories — twelve. Among contiguous countries Russia has the most, at eleven, followed by the United States and Canada at six each. China is the notable outlier in the other direction: it spans five geographic zones but runs the whole country on one, Asia/Shanghai.
Why does this site list more IANA zones for a country than the number of time zones it is usually said to have?: Because the IANA database splits a zone whenever any part of it has had a different history of clock changes, not only a different offset today. The United States is usually described as having six zones, but IANA carries entries such as America/Indiana/Indianapolis and America/North_Dakota/Center because those places switched zone or daylight-saving rule at some point. They agree with their neighbours on the current offset and differ only on past dates.
Do all countries observe daylight saving time?: No — most do not. Daylight saving is largely a European and North American practice, along with parts of Australasia and a handful of countries elsewhere. Almost all of Africa and Asia keep a fixed offset year-round, and several countries have abolished it in recent years. Each country page states which of its zones observe it and when the next change falls.
Why does the difference between two countries change during the year?: Because the two ends move on different dates, or only one moves at all. London and New York are five hours apart for most of the year but four for a couple of weeks each March, when the United States has already changed its clocks and Europe has not. Between hemispheres the swing is two hours, because the two sides move in opposite directions.