Hi. This is Cathy with Level Up RN. In this video, I will explain why military time is used in the hospital setting and how to convert from military time to standard time and from standard time to military time. You can find all the information that I'll be covering in this video in our Level Up RN dosage calculation workbook. If you are in nursing school, then you know how important it is to master dosage calculations, and our workbook will help you do just that. For more information about our workbook, you can click here. But in a nutshell, our workbook contains all different types of dosage calculation problems that you are likely to encounter in nursing school. And we demonstrate how to solve each problem using multiple methods so you can pick the way that makes the most sense to you.
So in the hospital setting, we use military time, and that's to avoid confusion between AM and PM hours. So we start at 0000, which is midnight, and go all the way up to 2359, so which is 11:59 PM. So when we're going from military time to standard time, we're going to kind of use these rules right here. So if we're dealing with a military time between 0000 and 0059, we're going to add 12 hours, a colon, and an AM. If we're dealing with a military time between 0100 and 1159, we're going to add a colon and an AM and drop any leading zero that may be present. And then if we have a military time between 1200 and 1259, we're going to add a colon and PM. And then for a military time between 1300 and 2359, we're going to subtract 12 hours and then add a colon and PM. So let's work through a couple of examples.
With our first example, we have a military time of 1645, and we want to take that to standard time. So if you kind of look at our rules here, 1645 falls within this range here, which means we're going to subtract 12 hours and then add a colon and a PM. So if I take 1645 and I subtract 12 hours, I get 4:45. And then I just need to add that colon and a PM. So 1645 military time is 4:45 PM standard time. What about our second example? Here we have a military time of 0845, which falls within this range here. So we need to add a colon and an AM and then drop any leading zero. So we're going to take our 0845, we're going to add a colon, we're going to add an AM, and then we need to drop this leading zero. So this becomes 8:45 AM. So 0845 military time is 8:45 AM standard time.
All right. Let's now talk about how to go from standard time to military time. So these are kind of the rules that you need to follow. So if the standard time is between 12:00 AM and 12:59 AM, you need to subtract 12 hours, remove the colon and the AM. If you have a standard time between 1:00 AM and 11:59 AM, you simply need to remove the colon and AM. If you have a standard time between 12 o'clock PM and 12:59 PM, you need to remove the colon and the PM. And then finally, if you have a standard time between 1:00 PM and 11:59 PM, you need to add 12 hours and then remove the colon and PM. And no matter which of these things you follow, you need to make sure when you're doing military time that we have four digits. We have two digits for the hour and two digits for the minutes. So let's work through a couple of examples.
So our first example has a standard time of 6:30 AM, so that really falls within this range right there. So we need to remove the colon and the AM. So if we do that, we end up with 0630. But because we need four digits, two digits for the hour, two digits for the minutes, we need to add a zero on here. So 6:30 AM becomes 0630. Let's work through our second example. Here we have a standard time of 8:15 PM. So according to our rule here, that falls within this range. We need to add 12 hours, remove the colon and the PM. So if I add 12 hours onto this, I end up with 2015, right? So 8:15 plus 12 equals 2015. And then I want to get rid of the colon and the PM, so this becomes just 2015. So 8:15 PM equals 2015 in military time.
