List of the Time Zones

Key Facts

• There are 24 time zones in the world, each of which is one hour ahead or behind of the Coordinated Universal Time (UTC).
• Daylight Saving Time (DST): Many regions adjust their clocks forward during the summer months and back in the winter to make better use of daylight. This practice, known as Daylight Saving Time, can lead to time zone changes within the same region.
• UTC is the primary time standard by which the world regulates clocks and time. It is within about 1 second of mean solar time at 0° longitude, and is the basis for civil time today.
• Time zones are based on the Earth's rotation around its axis, which takes 24 hours.
• The Earth is divided into 360 degrees of longitude, with each degree representing one hour.
• The Prime Meridian, which passes through Greenwich, England, is the dividing line between the Eastern and Western Hemispheres.

Interesting Facts

• The largest time zone in the world is the UTC+12 time zone, which covers the International Date Line.
• The smallest time zone in the world is the UTC−12 time zone, which covers the Baker Islands and Howland Island.
• There are a few places in the world that do not observe standard time zones. For example, Nepal uses a time zone that is 45 minutes ahead of UTC+5:45.
• The world's first time zone system was introduced in Canada in 1879.
• The current time zone system was adopted by the International Meridian Conference in 1884.
• China's Single Time Zone: Despite its vast size, China follows a single time zone (China Standard Time, UTC+8) across the entire country. This means that in the western part of the country, the sun rises and sets considerably later than in the east.
• Antarctica's Unique Time Zones: Antarctica's time zones are based on the locations of research stations. This results in an interesting mix of time zones on the frozen continent.