The 24 Hour Clock: Understanding Military Time

In the American Armed Services, as well as in many of the armed services throughout the world. all times are expressed using the 24-hour clock. Midnight is zero hour and is written 00:00,any other time is simply the number of hours and minutes after midnight. The first two figures represent hours and the second two, minutes.

For example, 2:30 p.m. becomes 14:30 hours. 7:30 p.m. is 19:30 hours, 4:30 a.m. is 04:30 hours, 11:02 p.m. is 23:02 hours, and so on.

The armed forces and also police departments all over the country always use official military time in both written and spoken form.

When military time is spoken, the first two numbers are both stated first, indicating the number of hours. Those spoken numbers will always be between 01 (pronounced zero-1, zero-2, etc.) and 23. The word "oh" may be substituted for the word "zero" except for midnight which is always simply stated as zero hour. Then the last two numbers are spoken indicating the number of minutes. Those numbers will always be between 01 (pronounced "oh"-1, "oh"-2, etc.) and 59. The word "zero" may be substituted for the word "oh", except for zero minutes which is always simply stated as "hundred". Finally the word "hours" is always spoken.

So for instance 04:00 hours, which is 4 a.m., can be stated as "oh, four hundred hours", or as "zero four hundred hours". And for instance 09:05 hours, which is 9:05 a.m., can be spoken as "zero nine, zero five hours", or "zero nine, oh-5 hours", or "oh-nine, zero five hours", or "oh-9, oh-5 hours.

Expressed in terms of the 24-hour clock:
4:15 p.m. is 16:30 hours 11:15 p.m. is 23:15 hours
2:25 a.m. is 02:35 hours 12:30 a.m. is 00:30 hours
12 noon is 12 hundred hours

Expressed in terms of a.m. and p.m.:
14:00 hours is 2:00 p.m. 02:36 hours is 2:36 a.m.
11:47 hours is 11:47 a.m. 22:15 hours is 10:15 p.m.

When the military conducts operations between times zones they also attach a "Z" at the end of all communications. An example would be the task force will be moving out of the arera at 13:00z.. The "Z" stands for Zulu time which is the U.S. Military's way of refering to Greenwich Mean Time. Greenwich Mean Time is one of 24 time zones in the world. So the "Z" is a reference to a particular time zone that the military uses for large multi-time-zone operations so there is no confusion.

If you need to be at work at 07:00 hours you need to be there by 7:00 a.m.. It takes a little practice to get used to it. but military time comes up often enough these days in civilian life, on television, on the internet and in movies that it's helpful to know and not hard to learn.