What is the BMR Calculator?

Your BMR (Basal Metabolic Rate) is an estimate of how many calories you’d burn if you were to do nothing but rest for 24 hours. It represents the minimum amount of energy needed to keep your body functioning, including breathing and keeping your heart beating. Below we will explore the BMR Calculator in more detail.

How to measure your BMR

Not to be confused for RMR, your basal metabolic rate or BMR is measured in calories per unit of time, and BMR is most often shown to you in calories burnt per day. When you measure your BMR, what you are measuring the amount of energy that your body consumes while at rest in a neutrally temperate environment, and in a post-absorptive state (meaning that the digestive system is inactive, which requires 12 hours of fasting). In a normal day, the closest you get to reaching your basal metabolic rate is when you are sleeping. Basal Metabolic rate is also known as your body’s metabolism or basal metabolism. Increasing your metabolic weight, such as exercise will increase your BMR. Next, we will talk about how to calculate your BMR.

Formula for the BMR Calculator

The BMR formula takes into account the variables of height, gender, age and weight to calculate your metabolism/BMR. You can then apply your activity factor to your BMR by using the Harris Benedict Equation so you can calculate how many calories you burn in one day.

What is my BMR?

To find your BMR fill in your numbers in the below fields. The calculator below will calculate your BMR for you. To embed the bmr calculator below in your own website or blog, customize the bmr widget. Otherwise simple input your numbers in the bmr calculator below:

BMR Calculator for Men

The BMR equation for men is more dependent on height and weight, so you can have larger fluctuations of calorie needs. Basal Metabolic Rate for Men = 66 + (6.23 x your weight in pounds x 1.15) + (12.7 x height in inches) – (6.8 x age)

BMR Calculator for Women

The BMR for women is less dependent on height and weight, which is why BMR is never less than about 1100 calories a day. Basal Metabolic Rate for Women = 655 + (4.35 x your weight in pounds x 1.20) + (4.7 x height in inches) – (4.7 x age)

BMR Chart

You may have noticed that as you get older your body metabolism slows. This is normal since your body’s metabolic rate decreases with age, an indication of the decline in energy utilization and production. Here is the BMR chart that graphically represents how your metabolism decreases with your age.

The BMR Chart including Basal Metabloic Rate and Metabolism Changes With Age

BMR Chart

Basal Metabolic Rate Summary

Your BMR is the calories you burn when you are at rest/while sleeping. You can calculate your BMR by using the Basal Metabolic Rate calculator. In the day of the average person, the BMR is responsible for approximately 60% to 70% of the total number of calories you burn. Please note that for athletes the bmr calculator would account for a smaller calorie expenditure than for sedentary individuals.


Andy is a weight lifting enthusiast with a passion for nutrition. He lives in the bay area with his family.

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