World Time Zones

Standard time zones of the world (click on the map to enlarge it), map from the World Factbook, CIA 2025. Names and boundary representation are not necessarily authoritative. West: Add time zone number to local time to obtain UTC (Coordinated Universal Time) or subtract time zone number from UTC to obtain local time. East: do the opposite.

There are time differences around the world based on “Coordinated Universal Time (UTC).” There are 24 regions (Time Zones) around the world with a time difference of one hour. This system has been adopted internationally by setting the total time difference around the world as 24 hours. UTC has been widely embraced by most countries and is the effective successor to Greenwich Mean Time (GMT) in everyday usage and common applications.