1. Home
  2. Science

How to Understand Military Time Quickly and Easily

We all know there are twenty four hours in a day. Yet we break out clock into two cycles of twelve. We use an am and pm suffix to denote which of the two cycles we are on. Military time takes away the need for this by simply running on a full 24-hour format.

It's a Matter of Time

Unless you’re in the armed forces, the emergency services, or grew up in a military household, you probably don’t encounter the use of the 24-hour clock very often. But what do you do if someone breaks out military time while setting up an appointment? In this article we will take a closer look at military time, what it is, how to tell it, and why is a useful system.

What is Military Time?

To put it simply, military time is the time based on the fact that there are 24 hours in a day. Rather than using ‘am – ante meridiem‘ or ‘pm – post meridiem‘ to specify the time of day on a 12 hour cycle.

Military time starts at 0000 – zero hundred hours – and ends at 2359. Following the same pattern as the more traditional am/pm time telling method.

When using military time you also use a hundred multiplier for the hour. Rather than just reading it like 8 o’clock in the morning you would say zero eight hundred hours. When written it would be 0800.

Why Do We Use Military Time?

Understanding How The Military Tell Time

The usage of military time began as a way to ensure accuracy when talking about times. There are a lot of different ways one could say nine in the evening. However, when you use military time those parameters get reduced to a single option; twenty one hundred hours.

When you are trying to communicate with large numbers of people in different groups all set in different parts of the world, you want to make sure you have a solid way in which to communicate time.

Sticking to a single system with a designator for the time zone reduces the margin for error significantly. A handy thing when planning battles or covert operations.

Who Uses Military Time?

The World Clock

While it is commonly called military time, its use is not exclusively limited to the armed forces. Many people from the emergency services and medical teams through to scientists, astrologists, and meteorologists use it as their primary means of time notation.

In fact, many European countries regularly used military time in their day-to-day lives. It is primarily the United States, Australia, the United Kingdom, and the Phillippines where the 12 hour clock is the dominant manner of telling civilian time.

Understanding Military Time Conversion

Simple Military Time Converter
via ATRRS Course Catalog

As with all things that require conversion, there is often an easier way and a trickier way.

For military time conversion, the simpler way to go from civilian time to military time. When you are talking about morning hours, you just turn the hour into a hundred, and once you go beyond midday you simply have to add twelve to the hour you are talking about.

So, one in the morning becomes zero one hundred hours, while one in the afternoon becomes thirteen hundred hours.

It’s interesting to note that military time always remains in hundred hours never thousands. So, 10am is ten hundred hours.

You can always get a handy military time chart to help you with any conversions you may need to do during the day.

To perform a military time conversion beck into civilian time you just need to subtract twelve from any time mentioned that is beyond twelve.

The simple way to think about military time is to just continue counting once you go beyond midday rather than resetting back to one.

Using Military Time

Understanding the 24-Hour Clock

While it may seem daunting to start with, once you get used to using military time then it will become second nature to you.

A good way to get used to using military time is to set your computer to display military time or the 24-hour time format. Reading the time is a great way to get the logic ingrained in your memory.

The ability to convert military time is invaluable, as you are going to come up against it at some point in time. It is becoming a more common way to express time as people realize how much less confusing it is when making plans.

When using military time across time zones, you always give the time in local time for where the event is taking place. Whether it’s a birthday party, a bombing raid, or a holiday to visit the in-laws.

How to Write Military Time

Military Time Written Down

When writing out military time, you should not use decimal hours. This is the main difference between writing time using the 24 hour system vs the true system used by military personnel. Traditionally you would write the time as 0000 for midnight, 0001 for 12:01, 0002 for 12:02 am, and so on up to the last minute of the day which is 2359 or 11:59 pm in ‘regular’ time.

So for example:

  • Three o’clock in the afternoon – 3pm – 1500hrs – fifteen hundred hours
  • Eleven o’clock at night – 11pm – 2300hrs – twenty three hundred hours

You can always get yourself a simple military time chart to reference until it comes second nature to you.

Military Time FAQ

What is military time?

Military time refers to the way in which those in the armed forces tell the time. Rather than using the AM or PM differentiator, military types use the 24-hour clock and thus do not reset to one once the hour goes past twelve. 

What is the difference between 4 am and 4 pm in military time?

When looking at a military time conversion chart, you will see that 4am and 4 pm are expressed as follows:

  • 4am – 0400 – zero four hundred hours
  • 4pm – 1600hrs – sixteen hundred hours

What is 7:30 pm in military time?

Military time is another way of saying the 24-hour clock. So, when converting regular time into the military time you need to add twelve to whatever time you are talking about. So, 7:30 pm would become 19:30. Because you use the full 24 hours, there is no need to use an identifying suffix to the time. 

In military time is it 2400 or 0000?

While both are correct and somewhat interchangeable, if you want to be correct with your usage of military time, then you should use 0000 or zero hundred hours to indicate midnight (or 12 am). 

What is Zulu Time?

Zulu time means the Zero Meridian, or Greenwich Mean Time (GMT). This is the time zone from which all other time zones spawn. Its real name is the zero meridian. When using the phonetic alphabet the letter Z is represented by the word ‘Zulu’. Those in the military and also the emergency services use the phonetic alphabet to avoid any confusion about what letters they are saying, so it became known as Zulu time.  

Final Thoughts on Military Time

Once you get used to working in military time, using the 12 hour clock feels wrong. There is definitely an adjustment period, but once you master it, you will never look back.

What is your time-telling experience? Are you a 12 hour clock fan, or a military convert? Let us know in the comments. We love hearing from you.

One comment