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24 hour clock

The 24-hour clock is commonly used in timetables and where space is restricted. It is used without ‘am’ or ‘pm’.

The 24-hour clock is a convention of time keeping in which the day runs from midnight to midnight and is divided into 24 hours. The 24-hour clock starts at midnight (00:00) and indicates the hours passed, from 0 to 23.

It is the most common system in use in the world, and is the international standard notation of time. (ISO 8601)

The 24-hour clock is used throughout to refer to specific services. Times are presented as HH:MM.

12-hour clock 24-hour clock
1.00am 01:00
2.00am 02:00
3.00am 03:00
4.00am 04:00
5.00am 05:00
6.00am 06:00
7.00am 07:00
8.00am 08:00
9.00am 09:00
10.00am 10:00
11.00am 11:00
12.00pm 12:00 (midday)
1.00pm 13:00
2.00pm 14:00
3.00pm 15:00
4.00pm 16:00
5.00pm 17:00
6.00pm 18:00
7.00pm 19:00
8.00pm 20:00
9.00pm 21:00
10.00pm 22:00
11.00pm 23:00
12:00am 00:00 (midnight)