BMR Calculator | How Much Energy Do You Need?

The BMR calculator below is also a meal plan generator. Once you enter your information and hit “calculate” you will see custom meal plans that are generated based on your ideal daily calorie intake.

This calculator is for informational purposes only and should be used only for estimations. Differences in calculations can have enormous clinical consequences. These tools do not give dietician, professional or healthcare advice. This information is not intended to replace clinical judgment or guide individual patient care in any manner.

Basal Metabolic Rate Calculator
Age   Years
Gender   Male       Female

What is a BMR Calculator?

Basal Metabolic Rate, also known as BMR, describes the amount of energy that the human body burns daily to maintain its vital functions just to survive.

In other words, it gives you an approximate number of calories you would burn if you spent an entire day doing nothing, the minimum amount of energy needed to keep the body alive, which includes vital functions such as breathing, digestion and heartbeat.

BMR calculator does not account for the energy you expend in your daily activities or exercise.

Imagine spending a whole day without any physical effort, on an empty stomach, at an ambient temperature of 20 °- 25° Celsius, in complete peace. Surprisingly, during that time, your body needs energy and burns calories anyway.

It does sound like a paradox that the body needs the most calories and energy while relaxed because every organ in our body is considered “a muscle”. The muscles need a lot of energy for their proper functioning.

You might find it surprising that about 70% of our calories are burned to maintain those daily physiological, vital functions of the organs, like breathing for the lungs, pumping for the heart, digesting for intestines, filtering the blood for kidneys and so on.

So, if you don’t eat enough, you risk leaving your organs without the energy to work.

The energy that the body burns during the day is called total daily energy expenditure (TDEE). This concept is divided into 3 groups: basal metabolism, thermic effect of food, and level of physical activity.

From which most of the energy goes to basal metabolism

When you know your BMR, you know exactly how many calories you burn during the day while at rest.

Thus, you can evaluate how many calories you need to take to increase muscle mass, lose weight, or maintain it.

Simply put, if you know how many calories you are taking in and burning, the path to a perfect body will be easier.

To find out the number of calories your body needs, you can use the BMR calculator or do the calculation yourself using formulas.

Remember that you can not know exactly what the BMR value is by using a BMR calculator.

The only way you can figure out your BMR results with 100% accuracy is through laboratory testing. The specialist will use indirect calorimetry that measures the rate of your oxygen consumption.

This test requires you to fast for 12 hours in advance and be at a neutral temperature to prevent sweating or chills.

You can visit a nutritionist for exact BMI, BMR, Fat %, lean muscle records, etc to plan a diet accordingly and accurately.

There are 3 main types of BMR calculator formulas:

The Mifflin-St Jeor formula

For men: BMR = 10 x Weight + 6.25 x Height – 5 x Age + 5

For women: BMR = 10 x Weight + 6.25 x Height – 5 x Age – 161

For this BMR calculator, we use the Mifflin-St Jeor formula, which is considered to be the most accurate and most commonly used BMR equation nowadays.

Revised Harris-Benedict Formula:

For men:

BMR = 13.397 x W + 4.799 x H – 5.667 x A + 88.362

For women:

BMR = 9.247 x W + 3.098 x H – 4.330 x A + 447.593

The older Revised Harris-Benedict Formula was introduced in 1984, although its popularity waned in the 1990s when newer more accurate formulas were presented.

This formula is likely to over and under-estimate results for very muscular or very obese people. Thus, it’s less commonly used nowadays.

Katch-McArdle formula

BMR = 370 +(21,6 x Lean Body Mass(kg))


In case you know your body fat %, the formula looks like this

BMR = 370 + 21.6(1 – Body fat %) x Weight

Recently, a newer Katch-Mcardle formula was developed, which differs from other formulas only in that it calculates energy expenditure during rest (RDEE), also taking into account muscle mass and body fat percentage.

This formula is more suitable for slimmer people who are looking to increase muscle mass. When used properly this formula is considered to be very accurate.

BMR Calculator – Factors that Affect BMR

BMR calculator - The Henry Equations

BMR calculator – The Henry Equations

BMR is influenced by several factors:

  • Weight – People with higher weight will get a higher BMR count
  • Body type – It is known that adipose tissue has a lower metabolic activity than muscle tissue. As muscle mass and body surface area increase, so does the metabolic rate.
  • Age – metabolic rate decreases with age; the reason for this is the loss of muscle tissue, the growth of adipose tissue, as well as hormonal and neurological changes.
  • Gender-basal metabolism in males is about 5-10% higher than in females. This is because women have more body fat than men of the same weight and height.
  • Genetics – you are more likely to have similar BMR as your parents or other first-degree relatives. Genetics play a huge role in determining your metabolic rate.
  • Body temperature – For every 0.5 ° C increase in body temperature, BMR increases by 7%.

The first step in calculating the number of calories is to calculate BMR using any of the three methods mentioned.

The second step is to find out your total daily energy expenditure (TDEE). TDEE is calculated by multiplying the final BMR number by the factor of your physical activity level. 

Here are the 5 types of physical activity levels:

Passive type – If you have minimal or no physical activity, multiply BMR by a factor of 1.2.

Minimally active type – If you train 1-3 times a week, multiply BMR by a factor of 1.375.

Moderately active type – If you train 3-5 times a week, multiply your BMR by a factor of 1.55.

Active type – If you train 5-6 times a week, multiply your BMR by a factor of 1.725.

Overly active type – If you are a professional athlete or train 6-7 times a week or have a physically demanding job, multiply BMR by a factor of 1.9.

The final number represents the energy requirement and daily calories needed to maintain weight. If you want to lose weight, you need to take in fewer calories and vice versa.

BMR calculator can also be used to have a general idea about your calorie deficiency calculation. When you calculate your BMR, you can see your minimum daily calorie needs based on your physical activity. Make sure to consult your physician before following a calorie deficient diet.

Weight loss in a healthy middle-aged individual depends primarily on maintaining a low caloric balance. What does this mean? It refers to consuming fewer calories during the day than our body needs. The average person’s energy consumption depends on three main factors:

  • Basal metabolism
  • Energy consumption from movement
  • Food calorimetry

Basal metabolism:

This refers to the energy expenditure generated by all the normal functions that the body performs every day to keep us alive.

Energy consumption from movement:

Energy consumption from movement is that which arises from any activity requiring physical effort in our lives, not just exercise, but also daily life situations such as climbing stairs and carrying something heavy.

Food calorimetry:

This is the energy consumption our body needs to carry out the digestion of food so that they can be processed, and digested, and thus allow the absorption of their essential nutrients in different portions of our digestive tract.


By using the Diets Meal Plan’s calculator, documentation and/or any software found therein, the User agrees to abide by Diets Meal Plan’s Terms and Conditions.

This calculator is for informational purposes only and should be used only for estimations. Differences in calculations can have enormous clinical consequences. These tools do not give dietician, professional or healthcare advice. This information is not intended to replace clinical judgment or guide individual patient care in any manner.

Your reliance upon information and content obtained by you at or through this website is solely at your own risk. Neither Five Buttons, LLC, nor shall be liable for any special, consequential, damage or injury (including death) to you, other persons or exemplary damages resulting in whole or part from any User’s use of or reliance upon this calculator and the information contained within.

Diets Meal Plan and the system’s authors, developers and distributors assume no responsibility for any erroneous results due to defects in the system. Access to and use of the Diets Meal Plan is provided without warranty of merchantability or fitness for any particular purpose or any other warranty, express or implied.

See Also

BMI Calculator