BMR Calculator
The BMR calculator is one of the tools used by many people who are on a weight loss journey. While counting calories and exercising, you might want to know how much energy (calories) your body consumes while you sleep.
Now, this used-up energy isn’t the same for everyone, but dependent upon certain factors like body weight, age, etcetera.
A BMR calculator is a tool that can be used to estimate the number of calories a person burns at rest. It can be useful for people who are trying to lose weight, gain weight, or maintain their current weight. This is because it can help them determine how many calories they should be consuming daily.
Whether you are trying to maintain a good weight or just want to know more about this calculator, this article is for you. In this piece, you’d learn about the BMR calculator, how it works, the equations it uses, and lots more.
What is BMR?
BMR stands for Basal Metabolic Rate. It is the minimum number of calories that your body needs to perform basic functions such as breathing, circulation, and digestion. Like the amount of gas a car burns to keep functioning.
However, unlike a car, the human body continues to perform these tasks even in a complete state of rest, such as sleep.
Therefore, the BMR represents the number of calories your body burns at rest. This is why it is often used as a starting point for determining your daily caloric needs.
That said, it is clear that your BMR doesn’t account for the calories burnt on chores, eating, or reading a novel. All energy that is used up by the body when conscious and active is excluded.
The BMR of healthy individuals varies between 5 and 10 percent of the mean. The mean BMR for healthy men, with a height of about 5’7″ is 1610, while that of women of the same height is 1430.

How does a BMR calculator work?
The BMR calculator uses your height, weight, age, and gender to calculate your basal metabolic rate. It does this by using a mathematical formula to compute your BMR. Then, the result is expressed as calories per hour per square meter of body surface area.
The basic rule is to multiply the weight of women in pounds by 10 and that of men by 11. So, if a woman weighs 120 pounds, then the BMR would be 120 x 10, which equals 1200 calories.
To get started, you’d have to fast for about 12 hours. This can be done easily when you have about 8 hours of sleep and a delayed breakfast of up to 4 hours.
At this point, you need to stand on a weighing scale to record your weight. The reading would be slightly lower than your weight before fasting. Next, you input this value into the weight section of your BMR calculator.
However, body weight and gender alone aren’t the only determining factor of a person’s BMR. Therefore, other equations were formulated to arrive at more accurate results.
One such mathematical equation used by some BMR calculators is Harris-Benedict’s equation. It is given as follows:
For women, the BMR is given as: 447.593 + [9.247 x weight (kg)]+ [3.098 x height (cm)] – [4.330 x age (years)]. While that of men is given as: 88.362 + [13.397 x weight (kg)] + [4.799 x height cm)] – [5.677 x age (years)]
Equations used by BMR calculators
Several equations for calculating BMR exist. The commonest equation used today is Mifflin St. Jeor’s method. It goes as far back as 1990 and is still in use today. It is given as P = [10.00 x m(kg)] + [6.25 x h(cm)] – [5.00 x a(years)] + s. Where:
P = the total heat produced by the body when at rest (sleep).
m = the body weight in kg.
h = the body height in cm.
a = the age of the individual in years.
s = constant, which is -161 for women and +5 for men.
The first equation was formulated by Max Keiber. He started research on mammalian BMR in the 1930s, and 1961.
He formulated a mathematical equation for it. Here he stated that the independence of mammalian BMR on total body weight (kg) is best expressed as 3.4 m exponential 0.75.
The exponential becomes 0.67 when the body surface area is analyzed. This led to his famous mouse-to-elephant line.

Other equations used by BMR calculators include that of James Arthur Harris and Fransisco Benedict’s BMR equation of 1919, which was revised in 1984. It is popularly known as Harris-Benedict’s equation.
Another is that of Katch MC-Ardle’s formula, which takes into account the resting daily energy expense (RDEE) and lean body mass. This makes it the most accurate of all the equations. It is given as follows:
BMR = 370 + 21.6(1 – F)W
Where:
F = the body fat percentage.
W = the body weight in kilograms(kg).
The downside to this formula is that it doesn’t take age, sex, and body height into account.
Factors that affect BMR Values
The BMR is influenced by several factors, including your age, sex, weight, and body composition.
Age
Little children consume lesser calories than teens and adults. As a result, they have lower BMR values. As you grow older, from a young adult into a senior citizen, your body consumes less energy. As a result, your BMR drops.
Sex
Gender is another factor that affects BMR values. Men and women of the same age range would most likely have different BMR values even if they are on a similar diet plan.
Many formulas used by common BMR calculators take this into account. Harris-Benedict’s equation is an example.
Weight
The more pounds you have, the higher your BMR, and vice versa. Body weight plays an integral role in the basic metabolism rate calculation. Therefore, all equations formulated by different scientists for this purpose take body weight into account.
Height
The taller an individual, the higher the BMR, and vice versa. However, this works in line with body weight as well.
A tall woman on the lean side may weigh almost the same as a short woman on the chubby side. Both women may have the same BMR value on computation if they are of the same age.
Muscle Mass
While you sleep, the body continues to work to keep vital organs functioning and including the muscles. So, a body with an appreciable muscle mass would require more energy (calories) to maintain compared to another with less.
Therefore, the BMR of individuals with heavily built-up muscles is higher than those of less muscular individuals. Little wonder why some weight loss experts recommend exercise to lose weight.
Supplements
Some supplements increase the BMR and thus aid weight loss. One such example is caffeine. Before you drown in cappuccino, do check with your doctor, as too much caffeine can raise your blood pressure and cause other health issues.
Weather
When the weather is hot, your body works extra hard to cool your entire system. When the weather is cold, it does the same to keep your body system warm.
This temperature regulation costs you some calories. Just like the cooling system for your car engine costs some gasoline. Therefore, the BMR increases when the weather becomes too hot or too cold.
Genetics
Some traits that are inherited from ancestors can increase or decrease the BMR.
Pregnancy
With pregnancy comes an extra living being your body becomes responsible for. So, while you rest, your body consumes energy to keep your little one and your vital organs functioning properly. This increases the BMR.

Diet
Eating small meals at short intervals would increase your BMR and, thus, aid weight loss. However, starvation reduces the BMR. According to experts, the BMR of a starving body can reduce by up to 30%.
Just like a phone goes into power-saving mode when the battery hits 10%. The human body reduces the amount of energy it consumes when there is a shortfall in the regular supply of calories.
BMR accuracy
Owing to several factors that influence the BMR value, the accuracy of online BMR calculators is questionable.
Although they might provide you with values to work within your weight loss journey. However, it is best to visit a specialist and get your BMR checked with a calorimetry device.
Conclusion for BMR calculator
To use a BMR calculator, you typically need to enter some basic information about yourself, such as your age, gender, height, and weight.
The calculator will then use this information to estimate your BMR and provide you with an idea of how many calories you need to consume each day to meet your goals.
It’s important to note, however, that the number of calories you need may vary depending on your activity level, so it’s always a good idea to talk to a healthcare professional if you have any questions or concerns.
You might also like…
Age (Max. 120 Years)
Gender
Feet
Inches
Weight (Max. 300 lbs.)
BMR Calculator
The BMR calculator is one of the tools used by many people who are on a weight loss journey. While counting calories and exercising, you might want to know how much energy (calories) your body consumes while you sleep.
Now, this used-up energy isn’t the same for everyone, but dependent upon certain factors like body weight, age, etcetera.
A BMR calculator is a tool that can be used to estimate the number of calories a person burns at rest. It can be useful for people who are trying to lose weight, gain weight, or maintain their current weight. This is because it can help them determine how many calories they should be consuming daily.
Whether you are trying to maintain a good weight or just want to know more about this calculator, this article is for you. In this piece, you’d learn about the BMR calculator, how it works, the equations it uses, and lots more.
What is BMR?
BMR stands for Basal Metabolic Rate. It is the minimum number of calories that your body needs to perform basic functions such as breathing, circulation, and digestion. Like the amount of gas a car burns to keep functioning.
However, unlike a car, the human body continues to perform these tasks even in a complete state of rest, such as sleep.
Therefore, the BMR represents the number of calories your body burns at rest. This is why it is often used as a starting point for determining your daily caloric needs.
That said, it is clear that your BMR doesn’t account for the calories burnt on chores, eating, or reading a novel. All energy that is used up by the body when conscious and active is excluded.
The BMR of healthy individuals varies between 5 and 10 percent of the mean. The mean BMR for healthy men, with a height of about 5’7″ is 1610, while that of women of the same height is 1430.

How does a BMR calculator work?
The BMR calculator uses your height, weight, age, and gender to calculate your basal metabolic rate. It does this by using a mathematical formula to compute your BMR. Then, the result is expressed as calories per hour per square meter of body surface area.
The basic rule is to multiply the weight of women in pounds by 10 and that of men by 11. So, if a woman weighs 120 pounds, then the BMR would be 120 x 10, which equals 1200 calories.
To get started, you’d have to fast for about 12 hours. This can be done easily when you have about 8 hours of sleep and a delayed breakfast of up to 4 hours.
At this point, you need to stand on a weighing scale to record your weight. The reading would be slightly lower than your weight before fasting. Next, you input this value into the weight section of your BMR calculator.
However, body weight and gender alone aren’t the only determining factor of a person’s BMR. Therefore, other equations were formulated to arrive at more accurate results.
One such mathematical equation used by some BMR calculators is Harris-Benedict’s equation. It is given as follows:
For women, the BMR is given as: 447.593 + [9.247 x weight (kg)]+ [3.098 x height (cm)] – [4.330 x age (years)]. While that of men is given as: 88.362 + [13.397 x weight (kg)] + [4.799 x height cm)] – [5.677 x age (years)]
Equations used by BMR calculators
Several equations for calculating BMR exist. The commonest equation used today is Mifflin St. Jeor’s method. It goes as far back as 1990 and is still in use today. It is given as P = [10.00 x m(kg)] + [6.25 x h(cm)] – [5.00 x a(years)] + s. Where:
P = the total heat produced by the body when at rest (sleep).
m = the body weight in kg.
h = the body height in cm.
a = the age of the individual in years.
s = constant, which is -161 for women and +5 for men.
The first equation was formulated by Max Keiber. He started research on mammalian BMR in the 1930s, and 1961.
He formulated a mathematical equation for it. Here he stated that the independence of mammalian BMR on total body weight (kg) is best expressed as 3.4 m exponential 0.75.
The exponential becomes 0.67 when the body surface area is analyzed. This led to his famous mouse-to-elephant line.

Other equations used by BMR calculators include that of James Arthur Harris and Fransisco Benedict’s BMR equation of 1919, which was revised in 1984. It is popularly known as Harris-Benedict’s equation.
Another is that of Katch MC-Ardle’s formula, which takes into account the resting daily energy expense (RDEE) and lean body mass. This makes it the most accurate of all the equations. It is given as follows:
BMR = 370 + 21.6(1 – F)W
Where:
F = the body fat percentage.
W = the body weight in kilograms(kg).
The downside to this formula is that it doesn’t take age, sex, and body height into account.
Factors that affect BMR Values
The BMR is influenced by several factors, including your age, sex, weight, and body composition.
Age
Little children consume lesser calories than teens and adults. As a result, they have lower BMR values. As you grow older, from a young adult into a senior citizen, your body consumes less energy. As a result, your BMR drops.
Sex
Gender is another factor that affects BMR values. Men and women of the same age range would most likely have different BMR values even if they are on a similar diet plan.
Many formulas used by common BMR calculators take this into account. Harris-Benedict’s equation is an example.
Weight
The more pounds you have, the higher your BMR, and vice versa. Body weight plays an integral role in the basic metabolism rate calculation. Therefore, all equations formulated by different scientists for this purpose take body weight into account.
Height
The taller an individual, the higher the BMR, and vice versa. However, this works in line with body weight as well.
A tall woman on the lean side may weigh almost the same as a short woman on the chubby side. Both women may have the same BMR value on computation if they are of the same age.
Muscle Mass
While you sleep, the body continues to work to keep vital organs functioning and including the muscles. So, a body with an appreciable muscle mass would require more energy (calories) to maintain compared to another with less.
Therefore, the BMR of individuals with heavily built-up muscles is higher than those of less muscular individuals. Little wonder why some weight loss experts recommend exercise to lose weight.
Supplements
Some supplements increase the BMR and thus aid weight loss. One such example is caffeine. Before you drown in cappuccino, do check with your doctor, as too much caffeine can raise your blood pressure and cause other health issues.
Weather
When the weather is hot, your body works extra hard to cool your entire system. When the weather is cold, it does the same to keep your body system warm.
This temperature regulation costs you some calories. Just like the cooling system for your car engine costs some gasoline. Therefore, the BMR increases when the weather becomes too hot or too cold.
Genetics
Some traits that are inherited from ancestors can increase or decrease the BMR.
Pregnancy
With pregnancy comes an extra living being your body becomes responsible for. So, while you rest, your body consumes energy to keep your little one and your vital organs functioning properly. This increases the BMR.

Diet
Eating small meals at short intervals would increase your BMR and, thus, aid weight loss. However, starvation reduces the BMR. According to experts, the BMR of a starving body can reduce by up to 30%.
Just like a phone goes into power-saving mode when the battery hits 10%. The human body reduces the amount of energy it consumes when there is a shortfall in the regular supply of calories.
BMR accuracy
Owing to several factors that influence the BMR value, the accuracy of online BMR calculators is questionable.
Although they might provide you with values to work within your weight loss journey. However, it is best to visit a specialist and get your BMR checked with a calorimetry device.
Conclusion for BMR calculator
To use a BMR calculator, you typically need to enter some basic information about yourself, such as your age, gender, height, and weight.
The calculator will then use this information to estimate your BMR and provide you with an idea of how many calories you need to consume each day to meet your goals.
It’s important to note, however, that the number of calories you need may vary depending on your activity level, so it’s always a good idea to talk to a healthcare professional if you have any questions or concerns.
You might also like…
Discover Investment Opportunities
Make your money do more.
Advertiser disclosure
Offers shown here are from third-party advertisers. We are not an agent, representative, or broker of any advertiser, and we don’t endorse or recommend any particular offer. Information is provided by the advertiser and is shown without any representation or warranty from us as to its accuracy or applicability. Each offer is subject to the advertiser’s review, approval, and terms. We receive compensation from companies whose offers are shown here, and that may impact how and where offers appear (and in what order). We don’t include all products or offers out there, but we hope what you see will give you some great options.
comparewise