Basal metabolic rate, sometimes also called resting energy expenditure, is the amount of calories you burn each day while at rest. This varies somewhat from person to person, but you can estimate it using your gender, height, weight and age. BMR usually makes up anywhere from 60 to 80 percent of the calories you use each day, with the rest coming from exercise and the calories it takes to digest and absorb your food.
How to Calculate Your BMR
First, convert your weight in pounds to kilograms by dividing by 2.2. Then, convert your height in inches to centimeters by multiplying by 2.54. If you're a man, to calculate your BMR you multiply your weight in kilograms by 13.7 and add this to your height in centimeters times 5. Subtract your age in years multiplied by 6.8 and add 66.47. This is an estimate of the calories you need to maintain basal function. For women, you multiply your weight in kilograms by 9.6 and add it to your height in centimeters times 1.8. Subtract your age multiplied by 4.7 and add 655.1 for your estimated BMR. If the math is a bit complicated for you, you can use an online BMR calculator.