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Which country has the most time zones?

I recently noticed quite a few hits on my website from people who wanted to know which country has the most time zones. I assume this was a school assignment of some sort.

The answer depends on the definition of "time zone." If a "time zone" is defined as simply an offset from Universal Time, then the answer is Russia (which has 11 different time zone offsets.) If a "time zone" is defined as "a location where the rules that determine the offset from moment to moment have been the same since at least 1970 or earlier" (which is the definition used by the Olson Time Zone Database, and is the one usually meant,) then the answer is the United States (which has 25 such time zones.)

Most countries only have one time zone, using either definition. Using the Olson definition, the only countries with more than one time zone are the United States, Russia, Canada, Australia, Greenland, Argentina, Brazil, Chile, Ecuador, Paraguay, Spain, Congo (Democratic Republic,) Mexico, Ukraine, Kazakhstan, Uzbekistan, Mongolia, China, Malaysia, Indonesia, New Zealand, French Polynesia, Micronesia and Kiribati.


Anonymous said...

I believe China only has one time zone despite its size...

Alan Lovejoy said...

China modernly only has one time zone offset--but in the past, there were different zone offsets in different parts of the country. The Olson definition of a time zone includes its entir3e history diachronically, not just its current characteristics.

Jérôme FROGET said...

France with 12.