24 hour clock
| 24-hour clock | 12-hour clock |
|---|
| 00:00 | 12:00 am |
| 01:00 | 1:00 am |
| 02:00 | 2:00 am |
| 03:00 | 3:00 am |
| 04:00 | 4:00 am |
| 05:00 | 5:00 am |
| 06:00 | 6:00 am |
| 07:00 | 7:00 am |
| 08:00 | 8:00 am |
| 09:00 | 9:00 am |
| 10:00 | 10:00 am |
| 11:00 | 11:00 am |
| 12:00 (noon) | 12:00 pm |
| 13:00 | 1:00 pm |
| 14:00 | 2:00 pm |
| 15:00 | 3:00 pm |
| 16:00 | 4:00 pm |
| 17:00 | 5:00 pm |
| 18:00 | 6:00 pm |
| 19:00 | 7:00 pm |
| 20:00 | 8:00 pm |
| 21:00 | 9:00 pm |
| 22:00 | 10:00 pm |
| 23:00 | 11:00 pm |
The 24-hour clock, also referred to as military time (only in the US) or continental time (only in the United Kingdom and now very rare), is a convention of time-keeping in which the day runs from midnight to midnight and is divided into 24 hours, numbered from 0 to 23. A time in the 24-hour clock is written in the form hours:minutes (for example, 01:23), or hours:minutes:seconds (01:23:45).
Under the 24-hour clock system, the day begins at midnight, 00:00 (12:00 am), and ends at 23:59:59 (11:59:59 pm).
The 24-hour clock has a number of advantages over the 12-hour clock:
- There is no possibility of ambiguity between times in the morning and evening (in the 12-hour clock "seven o'clock" means both 7 am and 7 pm). This is especially important for organizations that run services 24 hours a day, such as airlines, railways, and the military.
- The 12-hour clock writes noon as 12 pm and the midnight at the start of the day as 12 am: many people find this convention confusing. The 24-hour clock notates noon as 12:00, and midnight as 00:00 on the following day.
Note : There is no 24:00. 00:01 is the second minute of the day (00:00 being the first).
To convert between the 12-hour clock and the 24-hour clock, use the table to the right.
As well as military, public safety, and transport applications, the 24-hour clock enjoys also broad everyday civilian usage in many European and Latin American countries, and is widely used in establishing settings for computer operating systems. Many models of digital wristwatches and clocks are available that display the time of day using the 24-hour clock.
See also
