What countries are the furthest apart time-wise. For example Japan is ahead of EST by 13 hours. Is there time zones that differ by 24 hours? And what are they? If not then what are the furthest apart?

https://www.timeanddate.com/time/map/

For fun scoot your mouse down that jagged line in the middle of the Pacific where it is Thursday and Friday at the same moment :)

Considering major cities,

In Honolulu when the time is 1 p.m on Thursday, it's 8 a.m, Friday. The international date line lies between these two cities.

Yes, there are countries and regions that differ by a full 24 hours in terms of time zones. This is due to the fact that the Earth is divided into 24 time zones, each roughly 15 degrees of longitude wide. The International Date Line (IDL) is the imaginary line that separates two consecutive calendar dates and roughly follows the 180-degree longitude line.

One example of countries that differ by 24 hours are the United States (including Hawaii and Alaska) and the Pacific island nation of Samoa. The US Aloha State of Hawaii is located on the eastern side of the IDL, while the islands of Samoa are located on the western side. Hawaii is typically at GMT-10 or GMT-10:00, while Samoa is typically at GMT+14 or GMT+14:00. This means that when it is noon on Sunday in Samoa, it is noon on Saturday in Hawaii, resulting in a full 24-hour time difference.

Another example is Kiribati, a country made up of several island groups located in the Pacific Ocean. The Line Islands, including Christmas Island and Kiritimati, are located just east of the IDL and are at GMT+14:00. Meanwhile, the Gilbert Islands, including Tarawa, are located just west of the IDL and are at GMT+12:00. So, there is a 24-hour time difference between the Line Islands and the Gilbert Islands.

It's important to note that these are just a few examples, and there may be other regions or countries that also have a 24-hour time difference due to their location relative to the IDL. It's always a good idea to check the specific time zones of the countries or regions you are interested in to get accurate and up-to-date information.