BMR Calculator Calories To Lose Weight – Body Weight Tool

BMR Calculator Calories To Lose Weight

Making efforts to get fitter and lead a healthy life? Now that you have set out on a fitness journey you may feel the need to find a good nutritionist to guide you on calorie intake and deficits. But that would be costly and time taking, right? There are several calculators such as BMI, calorie calculator, etc that would help you just like a nutritionist.  

The BMR calculator to lose weight is one of the most useful calculators which we will be discussing in this article. One of the misconceptions we all have is that we only need energy when we are active and doing work. Truth is that our body needs energy even to perform basic functions such as breathing, blood circulation, digestion, etc. BMR calculator helps us to know the minimum amount of calories required to function such basic tasks while losing weight. 

BMR Calculator Calories To Lose Weight

How to calculate basal metabolic rate? BMR for lose weight is not as complex to understand only if you learn how this calculator can be useful to your fitness journey and how we can use it for this purpose. In this article, we will cover all the guidelines to use a BMR calculator calories to lose weight. 

What is BMR

What Is BMR

In simple words, basal metabolic rate (BMR) is the estimated energy that the body burns to fulfill basic bodily functions such as; 

  • Respiration
  • Breathing
  • Body temperature management
  • Digestion
  • Blood circulation
  • Cell production, etc.

A controlled BMR helps lead a sustainable life given that all the aforementioned functions will be performed with sustainability. It might be surprising for you to know that our body uses almost 70% of energy to maintain the function of vital organs such as the heart, lungs, kidney, nervous system, skin, etc. whereas only 20% is burnt for other physical activities. Thus, a person needs to take proper guidelines on BMR to lose weight. 

Difference Between BMR And RMR

Basal metabolic rate (BMR) and resting metabolic rate (RMR) are often used by some experts synonymously. Even though the two terms are closer in nature, there are minor yet defining differences between the two. 

  • Basal metabolic rate is the total number of calories that the body burns to perform basic life-sustaining functions. BMR is mostly observed and measured in a laboratory setting under certain set conditions over 24 hours.
  • While resting metabolism rate on the other hand is an estimate of the number of calories burnt in a state of inactivity. RMR is not necessarily calculated in a laboratory. It is calculated in a naturalistic setting ideally before breakfast in the morning.

We can say that the above definitions of BMR and RMR are somewhat the same things and can be used interchangeably. The resting metabolic rate is essentially an accurate measure of your basal metabolic rate. 

What Can Affect Your Basal Metabolic RateWhat Can Affect Your Basal Metabolic Rate

Basal metabolic rate calculator or BMR is not a constant and stable figure, rather it can change; increase, or decrease depending on certain factors within and outside of your body. Let us look at these factors one by one; 


GeneticsGenetic influence is in almost everything that your body consists of as well as your BMR. For example, scientists have found that people born in the Southeast Asian regions (China, India, etc.) have a slower metabolism as compared to people born in the western regions such as Americans and Brits. 

Body Fat Percentage

Your body fat percentage has an inversely proportional relationship with your BMR meaning that the lower the body fat the higher the BMR and vice versa. There are two categories of body fat. You can also check out our informative guide on how to measure body fat calculator online to keep track of your body fat and reach the optimal body fat percentage.

  • FFM: FFM stands for “fat-free-mass and it refers to the body weight without any effect of the fat tissues on it. A fat-free mass has a higher BMR compared to the other category we are about to discuss.
  • FM: FM stands for “fat-mass” and it refers to the body weight which only includes all the fat in our body. Even though this has a lesser effect on our BMR, it does count as one of the factors decreasing our BMR.


GenderGender is one of the defining factors in BMR weight loss calculator. Men are considered to have a statistically higher BMR as compared to women because men have a relatively greater muscle mass, which requires more energy to burn, compared to women who have a greater body fat than muscles. 


AgeYour basal metabolic rate tends to decrease with increasing age which is why children and young people have a higher BMR as compared to adults or aged people. Researchers believe that this is due to the change in body composition; the fat-free mass drops and eventually BMR decreases.                                                                                                                    

Muscular Exercises

Muscular ExercisesMuscular exercises such as weight lifting can be a great factor affecting your basal metabolic rate. This is because such exercises can help build more muscle mass and decrease fat mass which in turn increases your metabolism. 

Body Surface Area

Body Surface AreaThe greater the body surface area, the higher your basal metabolic rate will be. For example, people who are tall with lean bodies have a higher BMR. Whereas people who are short and weigh more have a lower BMR. This is why you see some people who are very lean even when they eat a lot. 

Body Temperature  

Body TemperatureHave you ever wondered why a sick person with a fever requires more energy and nutritious food? Your body temperature has a lot to do with the amount of energy your body uses to perform better. Every time your temperature rises even by 0.5o C, your body’s BMR increases up to 7%. 

 External/Climactic Temperature

External_Climactic TemperatureWhen the body is exposed to a colder temperature, its BMR tends to increase because in cold temperatures the human body utilizes more energy to maintain the needed amount of heat in the body. Similarly, exposure to hot temperatures will also result in a higher basal metabolic rate and vice versa. 

Diet And Eating Habits

Diet And Eating HabitsFood is one of the most essential factors that can affect your BMR. The lesser you eat and the pickier you are in eating, the lesser the BMR/metabolic weight would be. A starvation diet, as well as a low-calorie diet, can result in your BMR dropping up to 30%. Similarly, the BMR of people whose diet is vegetable-based has 11% lower BMR compared to those with meat-based diets. 

Hormonal Factors

Hormonal FactorsHormones are the byproducts of glands in our body that regulates different organs to perform sustainably. The most effective gland in terms of our BMR is the thyroid gland. When there is a higher rate of thyroid in your blood, your BMR tends to increase and it decreases when the glands are in a lower rate. 


DrugsBy drugs here we mean the common drugs that go into our body through a cup of coffee or tea. Caffeine and nicotine intake can result in an increased BMR and vice versa. 

Anxiety And Depression

Anxiety And DepressionMental factors such as anxiety and depression also affect your BMR to a greater extent. These states of mind increase muscle tension requiring more energy and release norepinephrine which also increases the BMR. 

How Can You Calculate Your BMR? (By equation)

Since now, you know what good BMR is and what can affect your basal calorie calculator, we shall move to the most important discussion on how you can calculate your BMR with the BMR calculator calories to lose weight. For this purpose, we will provide you with some equations or calculators with their respective variables.  

Harris-Benedict Calculator (Total Daily Energy Expenditure)

The Harris-benedict calculator calculates your daily calorie requirement to lose weight by multiplying your BMR with the total activity factor. This is the most frequently used BMR calculator formula. Following are the variables required for this equation: 

  • Gender
  • W= Weight
  • H= Height
  • A= Age
  • Total activity factor


Calculate BMR

Gender: Male Female

Refer to the following chart for finding out your total activity factor: 

Activity Level   Activity Factor Number  Description 
Sedentary  1.2   Very little to no exercise 
Lightly Active  1.375  Exercise at least 1-3 times a week 
Moderately Active  1.55  Exercise 3-5 days a week 
Very Active   1.725  Energetic exercise most days 
Extra Active  1.9  Exercise 6-7 days a week 

Now let us look at the equation: 

  • For man: BMR = 66.5 + (13.75 * weight in kg) + (5.003 * height in cm) – (6.75 * age)
  • For women: BMR = 655.1 + (9.563 * weight in kg) + (1.850 * height in cm) – (4.676 * age)

 Mifflin-St Jeor Equation

These days the Mifflin-St Jeor equation is quite famously used to measure your BMR. The variables that you need to find out to insert in this equation are almost similar to that of the Harris-benedict calculator. They are; 

  • Gender
  • W = Weight
  • H= Height
  • A= Age

The equation is as follows: 

For men: BMR = 10*W + 6.25*H – 5*A + 5 

For women: BMR = 10*W + 6.25*H – 5*A – 161   

Katch-McArdle Formula:

For people who are leaner and who know their body fat percentage, this equation is more suitable than the above-mentioned ones. It uses the following variables: 

  • W = body weight in kg
  • H = height in cm
  • A = age
  • F = body fat in percentage

The equation is as follows: 

BMR = 370 + 21.6(1 – F) W 


Following are a few things, which you can do to boost and increase your BMR. 

Weight Training And Exercise

Weight Training And ExerciseWhen losing weight, we tend to lose a lot of our muscle mass. This may affect your basal metabolic rate as it decreases with decreasing muscle mass. Therefore, when losing weight it must be kept in mind not to lose muscle mass. For this, you can opt for exercises such as weight lifting, high-intensity interval training (HIIT), circuit training, etc. at least twice a week. 

Protein-Based Diet

Protein-Based DietAnother very effective way to increase your BMR calories is to add more protein-based food to your diet such as seafood, eggs, whole grain, etc. This will help increase metabolism as it prevents overeating and thus gaining less fat. It also helps build your muscles. 

Drink More Water

Drink More WaterStudies have shown that dehydration can result in slow metabolism. Thus drinking more water can help make you feel full. However, drinking water in the daytime is much more beneficial to your metabolism as compared to nighttime. 

Take A Good Sleep

Take A Good SleepPeople who sleep less have a lesser metabolic rate. While sleeping, our body tends to burn more calories as it digests quicker. Thus, the more you sleep the higher your BMR would be. But quality sleep is better than quantified sleep, which means that night sleep is much more beneficial as compared to daytime sleep for your BMR. 

Frequently Asked Questions

A higher basal metabolic rate means that you have to burn more calories for your body to function sustainably in a day. 
A good BMR for a woman is 1409kcal while for men it is 1696kcal. 
The answer is yes. However since your BMR is just the amount of calories your body burns while it is at rest, this will not be a sustainable way to lose weight. 
NO, lower BMR means that your metabolism is slower, and it will affect how well your organs perform. 

Final Thoughts

In the end, I can say that this article will be your last stop to calculate your BMR ( body to mass ratio ) to figure out the right amount of calories that your body needs so that you can cut some calories to lose weight fast.

About the author

Amelia Robert

My name is Amelia Robert, and I am the co-founder and author of the website For the past seven years, I’ve been a certified personal trainer. I am really passionate about assisting women and men in achieving sustainability and happiness in their lifestyles, all while making progress in their own fitness journeys! My goal is to deliver the most accurate information in a way that motivates you to take an active role in your health and fitness journey.

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