Nursing Math Formulas

nursing math formulas

Nursing is a profession that requires a substantial amount of knowledge from a variety of different subjects. Many people think that nurses only need to focus on anatomy and physiology; however, subjects like math are heavily involved due to the need to calculate dosages, convert units, understanding different measurement systems, etc.

If you’re a nursing student currently in a nursing program, all of these formulas and units can be quite intimidating, especially if you don’t have a lot of previous experience with math, or math is simply not your strength. If you fall into this category, don’t worry! There are lots of nursing math resources out there that can help simplify topics and get you on your way to feeling more comfortable with the math you will encounter as a nurse.

Even if you generally feel comfortable with math and can usually understand formulas presented to you, it can be hard to retain this information over long periods of time without any sort of practice, especially as things change with time (e.g. ranges of lab values). Having nursing math review resources available can really come in handy, especially if you’re going back to school for a nursing program, or you are rotating through different units that often call on different math formulas for drug calculation and preparation.

Therefore, in this article, we will provide you with our Top 5 picks for the best nursing math review books and resources to help keep your mind numerically sharp! We will present a couple different styles, so these aren’t ranked in any particular order. Below our reviews, we will briefly discuss some nursing math study tips, so feel free to check that out as well!

Davis's Basic Math Review for Nurses: with Step-by-Step Solutions

Davis’s Basic Math Review for Nurses is arguably the most popular math review resource for nurses, mainly prospective nurses, currently on the market. This will vary by program, school, country, and type of nursing, but this is known to be a valuable resource for any nurse looking to brush up on their math.

This book has a lot of simplified information on basic math such as dealing with fractions, ratios and proportions, percentages, household measurements, metric system, multi-step equations, etc. Many people have found this book to be especially good for the HESI exam, especially if they haven’t used this sort of math in a while. Moreover, if you’re like me and have become largely dependent on a calculator, this book will help you regain the skills to perform those types of calculations quickly and easily without the assistance of a calculator, which you may not have quick access to on the job.

The main downside of this nursing math book is the limited information on drug calculations. There are no problems sets with drug calculations, so the material in this book is actually meant to bring you just to that point. It will give you the tools you need to know the fundamentals of how to perform these types of calculations, but doesn’t go into specific examples.

Overall, this is a great book for nurses looking to brush up on the basic math skills. It’s very affordable and especially effective for preparing you for the HESI exam. The solutions provided in the book are excellent, as they are broken down step-by-step, allowing you to understand every little detail of the problem you are currently working on.

Math for Nurses: A Pocket Guide to Dosage Calculation and Drug Preparation

Math for Nurses – A Pocket Guide to Dosage Calculation and Drug Preparation is a math review book that is highly applicable to a nurse’s clinical work. Similar to Davis’s Basic Math Review for Nurses, this book starts of by covering some basic math skills, providing you with a refresher before getting into the nitty-gritty.

We like this book because it uses a very systematic style of presentation. Starting from basic and progressing to more advanced or detailed information, this book is well organized and has a logical flow. Moreover, this addresses the Davis’s book’s lack of information specific to drug calculation. This Math for Nurses book uses a step-by-step approach with specific examples to help you calculate dosages effectively, ultimately improving the accuracy of drug delivery.

While this book is structures in a logical and easy-to-read way, it’s also surprisingly comprehensive. It allows you to learn about and practice calculations using various different methods, for example, ratio, proportion, formula, and dimensional analysis. There are lots of practice questions, both throughout the text, as well as review practice questions at the ends of chapters and units. Furthermore, it comes with a handy little pull-out quick-reference card for basic equivalents, conversion factors, and of course, math formulas.

Overall, this is a great nursing math review book for any nurse, whether you are a student or working professional, and the focus on dosage calculations and drug preparation is highly applicable to the job. There is a little bit of a review of basic math for nurses at the start of the book, but it quickly gets you going on the drug calculations. This book comes highly recommended by many different nursing student and professionals.

Dosage Calculation Workbook: Math Review and Practice for Nurses

The Kaplan Dosage Calculation Workbook is more similar to the Math for Nurses (Mary Jo Boyer) than the Davis’s book, in that it places a large focus on calculations to do with drug dosages, preparation, and delivery. It’s great not only for nursing students, but also working nurses who want to maintain proficiency in any of their work that revolves around administering medications. Kaplan is also known for their learning resources, so it could be a good option if you are approaching that particular exam.

This book isn’t necessarily better or worse than the one we reviewed above, it simply provides a different perspective and a few different pieces of information. For example, this Kaplan book includes dosage calculation practice questions using dimensional analysis, ratios, proportions, and formula methods just like the one we reviewed above, but it also provides practice problems for oral, IV, and parental administration of medication. There are broken down examples with step-by-step instructions, as well as quizzes at the end of chapters to help you gain a sense of what you do and don’t understand properly.

We like the overall structure of this book, as it starts out with some basic math questions to help you quickly identify where you need to improve in order to move on and fully understand the drug calculations. The book will help you identify this based on your answers, and will then provide information on any areas you may be weak in, ensuring you have a solid knowledge base before moving on and potentially overwhelming yourself. Once you get into the drug calculations, perhaps the feature we like most is that they show numerous ways of doing a single problem, so that you can play to your strengths and learn a method that works best for you.

Overall, this is a great nursing math review book that can be helpful for any type of nurse, wither you’re currently a student or have been an RN for many years, this can act both as a learning resource and a quick refresher, depending on your needs. It’s highly specific to drug calculations, and incorporates a variety of situations that you may be likely to encounter, making it highly applicable to the job.

Medical Math (Laminated Reference Guide; Quick Study Academic)

BarCharts is a company that makes a lot of these handy reference pamphlets for medical professionals. You will see another slightly different one below. They are very affordable, especially if you can find them online instead of a university bookstore (the latter of which tend to get as much money from students as possible). Also, they represent a quick and convenient way to access the information that you need.

This version of the pamphlet – The Medical Math Quick Study Pamphlet – is marketed towards anyone in a medical profession that will need to use any form of math. It has calculations, formulas, measurements, dosages, rates, equivalents, and more. Specifically, this pamphlet is broken down into six pages, and the guides place some emphasis on basic math (like the start of the books reviewed above), calculations and formulas, coding measurements, pediatric definitions, and clinical indicators.

One of the underrated features of this medical math pamphlet is the common abbreviations that you may encounter when needing to perform calculations. There is also supplemental information like needle lengths and gauges, APGAR scoring, childhood milestones, etc. That being said, some nurses have said they would like to see more formulas for calculating medications and IV dosages, and the print is really small, so it’s tough to read from fairly far away (e.g. if you have it on a wall somewhere).

Overall, this is a great resource that we think is probably a little better for nursing students than for seasoned RN’s. That being said, both have found benefits to this pamphlet, and with some basic understanding of the math involved in the nursing field, the info presented on these pamphlet cards allows for quick and easy reference.

Nursing Math (Quick Study Academic)

This is the same type of reference pamphlet is the one we reviewed just above this. Also made by BarCharts, this pamphlet is intended to be used specifically by nurses, rather than medical professions in general. Rather than a wide variety of fundamental information about math in the medical world, this package is a three-panel guide that focuses on nursing math formulas and equations, their definitions, step-by-step instructions, and helpful charts and tables for quick reference.

Given the more nursing-specific information, we think this could be great for both nursing students and seasoned RN’s, but we imagine this being more heavily used by a nursing student. For example, a student could have this over their desk or study area at home, so that when they are studying the material or working on assignments, the nursing math quick study pamphlet can be easily viewed and quickly referenced. However, there are limitations to this, as the print is fairly small once again.

While we consider these BarChart math review guides to be excellent, they do require a decent knowledge base to optimize their use. Even though they both contain some basic math information, for example, the Nursing Math Chart begins with multiplication, division, and fractions, it is still a little bare for those looking to really grasp the concepts. These charts are best used as a reference, whereby you can quickly look something up for a calculation, and therefore, we suggest learning a little about nursing calculations before buying these charts, simply so you can use them most effectively.

Overall, these are great learning and reference resources for nurses or anyone who needs to know more about math in the medical and/or nursing professions. They are especially great for students currently learning the material and want a supplement to their standard learning packages, but they can also be good for working professionals who simply want a quick refresher from time to time in order to maintain confidence and accuracy of medication delivery.

Nursing Math Formulas - Study Tips

Give Yourself Lots of Time

Making sure you have enough time to study is extremely highly recommended for various reasons. First, if you’re just starting to learn the material, there’s no knowing how long it will take to learn. How long it took for someone else may be different from you. Furthermore, if you set aside time based on how long it took you to learn the material thus far, you could still end up running out of time if you get stuck on one particular aspect of the material. Math can be tricky, and sometimes study breaks are necessary in order to clear your head, so just try and leave yourself a good amount of time for studying.

Learning the Theory Helps

When studying any sort of math, this was always my weakness. Learning the theory behind the math, that is, why we use certain formulas, and why certain formulas are written the way they are, can all be really helpful information, especially for an exam.

It is certainly possible to memorize formulas and procedures for calculations, but if something ever deviates from the classic examples you have been learning from, it can be really difficult to then subsequently do any problem solving. If you know why you are using certain formulas and how the terms in those formulas relate to each other, then you will definitely have a deeper understanding of the material and will be able to apply that knowledge in more situations.

For example, let’s take the body mass index (BMI) calculation. Let’s say you already understand that if you take two people of the same height, but one person is much heavier than the other, the heavier person will have a higher BMI. This must mean that the person’s mass is on the top part of the equation (numerator), while their height^2 is on the bottom (denominator), which will give you your units of kg/m^2. Conversely, if you know the formula, but haven’t heard anything about BMI before that, this can work in the opposite direction as well. For example, “I know that height^2 is the denominator. This must mean that increasing height will subsequently decrease the overall BMI, assuming height is constant.”. Working through problems and thinking about their real-life use can be quite effective for some people.

The main reason why this took me so long to build into my study habits was because learning the theory can take some time, which brings us back to our first point. It’s way easier said than done to learn the theory, especially if you are currently taking a full course load or just have a lot of other things on the go. Making extra time to study boring material in more detail is a challenge, let alone when you have lots of things to take care of, but if it’s possible to manage your time this way, we highly recommend trying to learn in this manner. It worked for me, but I’m just one person with my own style of learning.

Relax and Don't Be Intimidated

How often do you hear “I knew the material, I just froze on the test”, or “These formulas are so complicated, I just can’t wrap my head around them!”. These types of mentalities are very common, and certainly justified. However, for many people (not all), a big reason why they struggle with math, particularly with understanding and applying formulas, is because they see a jumble of symbols that’s essentially a different language to them. In this situation, it’s really easy to panic, even if you don’t fully realize it, and with your eyes jumping all over the page and an increasing feeling of self-doubt, it can be very difficult to study effectively.

Our suggestion? As vague as it sounds, we think the best thing to do is simply try and relax. These formulas are written the way they are for a reason. They are as condensed and simplified as possible without removing any information that is necessary to perform the calculations, even if it doesn’t seem that way at first. I have personally had success in many math courses from calming down and trusting that I can learn the material if I just take it slow and go one step at a time.

I find this helps for me: When you first learn about a particular mathematical process, and you move on to an example or practice question that looks intimidating, just take a breath and and start by studying the formulas involved. Being with identifying all the symbols and terms. Do you understand all of the symbols and terms in the formula? If not, look up those symbols or terms individually before working through the problem.

Then, move to the next step. What information do you already have? Is there any missing information in the formulas? For example, what if BMI is a term in a formula, you need that information to proceed with the calculation, but you don’t have it? Don’t panic, and look for any other information that could help. In this case, maybe you have information about the patient’s height and weight (or more appropriately, mass). If you have these pieces of information, you can calculate BMI on your own, and then use that number in the formula.

This is just one random example, but I have found this approach works quite well, especially when I see a question written in a way that I have never seen. Often times on different math exams, the questions will be spun in a way that makes it feel unfamiliar, but if you take your time and work through the math logically, you can often see clues of how to continue answering the question as you progress.

Understand the Importance

This is another one I’ve heard a lot, and admittedly, have said a lot myself: “Why do we need to know this?”. While this is less important for correctly answering a question on a test, understanding the clinical importance of different formulas and mathematical procedures can help you narrow own what is most likely to be asked, and can also serve as good motivation to study. Assuming you want to perform well in your job after graduating, it will be helpful to have as complete of an understanding as possible upon entering the work force.


At the end of the day, everyone has different studying styles and habits that work best for them, and these can be constantly changing as well. The information we provided above may not work for everyone, but hopefully it will at least get you thinking about your study habits and any sort of review process you think may be necessary in refreshing your memory on lots of this math stuff. Additionally, the resources we reviewed above for nursing math formulas aren’t the only ones out there, but we would consider them to be reliable options that are generally well-liked in the nursing community. Find something that works for you, and go with it! Good luck!

Also please take a look at our list of books and resources for Spanish for Nurses here – plenty of updated reviews have been added here recently.