How many standard time zones exist?

Joe Sam Shirah

Actually there are 25. The unexpected "extra" one comes about because there is a time zone for UTC+12 hours and one for UTC-12 hours. The International Date Line cuts through the middle of these two zones ( ignoring national line movements ) and these are often seen as covering 30 minutes or 7.5 degrees each because of the overlap and split. For more information, see: Time Zone Abbreviations.