How to Calculate Military Time [The Bottom Line]
Calculating military time is simple as it is based on 24-hour clock. To begin with, military time starts at 0000 (pronounced as “zero zero zero zero hours”) and ends at 2359 hours (pronounced as “twenty-four hundred hours”). This is similar to the 24-hour clock’s 00:00 to 25:59 found on digital watches and smartphones.
The main advantage of military time is clarity. For instance, when I say, “John woke up at 5”, it may mean John woke up at 5 in the morning or 5 in the evening. We simply assume that the activity that accompanying the time mentioned will clarify. For example, with the statement, “We will be having breakfast at 8”, we can identify the time as 8 AM since that is when we have breakfast. There are instances where this can lead to confusion. Like in the example with John, most people will assume John woke up at 5 in the morning, but this can be wrong. Military time helps prevent ambiguity.
Because of its accuracy and clarity, the military uses military time. Hospitals and law enforcement have adopted it as well.
What Is Military Time?
Military time is a format used to tell time that uses a 24-hour clock convention. In place of a 12-hour clock that resets twice in a day (i.e. 12:00 PM to 11:59 AM, and then from 12:00 PM to 11:59 PM), military time uses a 24-hour clock that commences at 0000 and ends at 2359 (a minute before midnight) and then resets at 0000 again.
Therefore, 2 AM in military time is 0200 while 1 PM is 1300. It is important to note that, midnight is not 2400 in military time rather it is 0000.
With military time, ‘hours’ can be placed at the end of the time mentioned such as ‘1300 hours’; this is optional and it can be omitted.
How to Understand and Write Military Time
Now that we know how to read military time, we need to know how to write and understand it. Remember, when writing military time, there is no colon separating the hours from the minutes.
How to Write the Hours from 12 Midnight to 12 Noon (12 AM To 12 PM)
In military time, writing the hours starting from midnight to noon is as simple as attaching a zero in front of the hour, removing the period (AM), and then attaching a double zero to the end. This, however, works with single digit hours only (i.e. 1 AM to 9 AM). For double-digit hours excluding 12 AM (i.e. 10 AM, 11 AM, and 12 PM), you simply attach a double zero to the end, for example, 10 AM will be 1000 hours, and 11 AM will be 1100 hours.
For midnight (12 AM), the military time is 0000 hours.
Here are some examples to help clarify
- 12 AM becomes 0000 hours.
- 3 AM becomes 0300 hours.
- 5 AM becomes 0500 hours.
- 8 AM becomes 0800 hours.
- 10 AM becomes 1000 hours.
- 12 PM becomes 1200 hours
How to Write the Hours from 12 Noon to 12 Midnight (12 PM to 12 AM)
Since we covered 12 noon already, we will start from the afternoon to midnight. Converting the Post Meridiem (PM) time period can be slightly tricky. Instead of starting the twelve-hour cycle post noon, we just continue counting. As such, since 1 PM is an hour after 12 noon, it is 1300 hours in military time. 2 PM is 1400 hours, 4 PM is 1600 hours, 5 PM is 1700 hours.
To quickly convert Post Meridiem hours (1 PM - 11 PM) to military time, simply add 12, then attach a double zero to the end.
Here are some examples to help clarify
- 1 PM becomes 1300 hours
- 2 PM becomes 1400 hours.
- 3 PM becomes 1500 hours.
- 7 PM becomes 1900 hours.
- 9 PM becomes 2100 hours.
- 11 PM becomes 2300 hours.
How to Read Military Time
Since the military time and the 24-hour clock are similar, knowing how to read one will make reading the other a child’s play.
How to Read the Hours
Standard time 06:00 AM is usually read as 6 in the morning, in military time this is 0600. You will read this as “zero six hundred hours”. As mentioned already, the ‘hours’ is optional and can be omitted. The 0 in front of the 600 may also be pronounced as ‘Oh’. It is required that you pronounce the zero in front of the hour when reading military time.
2:00 PM which is 1400 hours in military time will be pronounced as “fourteen hundred hours”.
To clarify, when reading military time, if the first digit is a zero, then you should mention the zero then the number that follows, then hundred hours. When the first digit isn’t a zero, then mention the first two digits as 1 number then follow that by hundred hours.
Here are some more examples to help clarify.
- 0300 hours is pronounced “zero three hundred hours” or “oh three hundred hours”
- 0700 hours is pronounced “zero seven hundred hours” or “oh seven hundred hours”
- 1200 hours is pronounced "twelve hundred hours."
- 1400 hours is pronounced “fourteen hundred hours”
- 2000 hours is pronounced "twenty hundred hours."
- 2300 hours is pronounced "twenty-three hundred hours."
How to Read the Hours and Minutes
When reading the time, you are most likely be required to say the minutes as well. When dealing with military time, many people find this tricky since they are not used to it.
You will need to divide the military time number into two distinct pairs of numbers. The first two digits are the hours, and the last two digits are the minutes.
Follow these procedures when reading both the hours and the minutes.
- When there are zeros before of the number, mention them. 0006 is “zero zero zero six hours" and 0013 is "zero zero thirteen hours."
- When there are no zeros before of the first two digits then you pronounce the first 2 digits as single number and the next two digits as another number. 1325 is pronounced as "Thirteen twenty-five hours" and 2222 is pronounced as "twenty-two twenty-two hours"
Converting Military Time to Normal Time
Now that you can read and write military time, it will be helpful to also be capable of changing military rime to regular standard time. As you may already know by now, any military time from 1200 onwards is in PM, while military time less than 1200 is in the AM. If the time is in the AM, you simply have to add the colon after the first 2 digits and then add the AM. For example, 1000 in military time means 10 hours and 0 minutes, and this becomes 10:00 AM in regular time.
If the time is 1300 and onwards, you first add the colon after the first 2 digits, then you subtract 12 from the hour portion of the time and attach PM at the end. As such, 1345 hours means 13 hours and 45 minutes and this becomes 1:45 PM in regular time. Feel free to check out lifehackers great article on the topic here.