For example, if you travel the 1061 km (659 mi) across the date line from Baker Island to Tokelau, you must add 25 hours, or 1 day and 1 hour. See the date line on our Time Zone Map Not Always 24 Hoursĭepending on which time zone the country follows, the time difference on either side of the line is not always 24 hours. If you traveled from Kiribati's capital Tarawa to Hawaii's state capital Honolulu, you would have to turn the clock back 22 hours, effectively traveling back in time, at least on the calendar. The International Date Line is the boundary where each calendar day starts and is also known as the “Line of Demarcation” because it separates two calendar dates: When you cross the date line traveling east, you subtract a day, and if you cross the line traveling west, you add a day.įor example, Kiribati and Hawaii are on different sides of the date line.

The Northern and Southern Hemispheres Different Days on Either Side For example, it leans towards the east at the Bering Strait between Asia and North America, leaving Cape Dezhnev in Russia a day ahead of Cape Prince of Wales in Alaska even though they are only 80 km (50 mi) apart. It is not straight but curves around landmasses and national borders. The date line runs from the North Pole to the South Pole and marks the Western and Eastern Hemisphere divide.

It is halfway around the world from the prime meridian (0° longitude), the reference point of time zones, which runs through Greenwich, UK. The International Date Line (IDL) is located at about 180° east (or west).

The International Date Line zigzags through the Pacific Ocean at around 180° longitude. Business Date to Date (exclude holidays).

World map time zone