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24-hour clock

What is the 24-hour clock?

The clock that does not hide the afternoon. 07:00 is morning; 19:00 is evening. Science, airlines, hospitals and most of the world use it because 7:00 on a 12-hour clock throws away the answer to breakfast or dinner. Convert any time on the 12- and 24-hour converter.

Who cannot afford the ambiguity

Write 7:00 on a board and ask: breakfast or dinner? You cannot know. Pilots, doctors, train drivers, armies, scientists: everyone whose mistake would matter uses the clock that keeps the afternoon.

This site’s timers and alarms can show either. The converter is the lesson: have a class write their day in 24-hour time and check it.

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Midnight is 00:00, not 24:00

24:00 is sometimes written for the end of a day, but civil time starts the new day at 00:00. UTC uses 00:00. So does this site.

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