BMR Calculator

Our BMR calculator below allows you to calculate the number of calories your body burns, before physical activity, on a daily basis.


BMR (Basal Metabolic Rate)


BMR (Basal Metabolic Rate)


BMR (Basal Metabolic Rate)


BMR (Basal Metabolic Rate)

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What is Basal Metabolic Rate?

You have likely heard of the Basal Metabolic Rate (BMR) but may not know exactly how it relates to your workouts or the best way to calculate it. Learn why BMR matters if you have pounds to shed or simply want to be healthy. Then, calculate your BMR with our handy calculator above.

Even when you sleep, you use energy. The BMR is the number of calories you would burn if you stay at rest all day, such as lying in bed. These calories reflect the amount of energy that your body requires to support its most basic, vital functions, such as breathing, blood circulation, and brain functioning. It excludes the calories you need for your workouts or other activities.

Why Does BMR Matter?

By knowing your Basal Metabolic Rate, you can figure out exactly how many calories you must burn for weight loss to occur. Of course, you already know that your metabolism affects your ability to lose weight; the faster your metabolism, the better your ability to burn fat. By understanding metabolic rate, you can welcome new weight loss opportunities.

Several factors determine your BMR:

  • Gender
  • Age
  • Height
  • Weight

When you lose weight, your BMR lowers, even if you are not losing weight on purpose. Every decade after age 30, your BMR declines by about two percent because humans stop growing bone. So, to stay at the same weight year after year, you would need to reduce your daily calories by that same amount. BMR accounts for approximately 60 percent of the calories you burn every day.

How to Calculate BMR

While it sounds complicated to figure out the rate of your metabolism, it need not be. There are online BMR calculators that do the work for you, taking out any guesswork, so you can determine how many calories you must burn on an average day to achieve the best health possible. This number is known as your maintenance level. Use the Mifflin St. Jeor equation to determine your Basal Metabolic Rate.

Research shows that the Mifflin St. Jeor equation is the better than the previous formulas at computing BMR. The Mifflin St. Jeor equation, which dates back to 1990, is today considered the standard formula.

To calculate your basic burn, the Mifflin St. Jeor equation takes into account your weight, height, and age – remember we listed these factors above? Gender is a factor because a woman’s BMR is usually 5-10 percent lower than that of a man. Regarding age, the metabolic rate declines as you get older. Height and weight are considerations because the more mass you have, the more energy your body needs to sustain its organs.


BMR and TDEE (Total Daily Energy Expenditure) are two closely related metrics but there is one main difference. The latter, TDEE, takes into account your Physical Activity Level (PAL). Your BMR is essentially your TDEE minus any physical activity of any kind, including exercise.

Computing the Mifflin St. Jeor Equation

The exact Mifflin St. Jeor formula is:

MEN: 10 x Weight (KG) + 6.25 x Height (CM) – 5 x Age (Years) + 5 = BMR

WOMEN: 10 x Weight (KG) + 6.25 x Height (CM) – 5 x Age (Years) – 16 = BMR

Or, you can simply use my online calculator, which uses the Mifflin St. Jeor equation. Now you have an idea of roughly how many calories it takes to keep your body alive at the level of basic functioning. Use your calculated BMR to estimate the dietary consumption you require to sustain your body weight, so you can look and feel your best!