How To Calculate BMR Manually

Your basal metabolic rate, also known as your BMR, is your minimum calorie expenditure rate, the rate at which you must expend calories in order to stay alive. Your BMR assumes you're in the post-absorptive phase of digestion, meaning you aren't actively digesting food. You'll typically need to know your BMI when you design a weight-loss to plan so that you can predict your weight-loss rate. You can calculate your BMR from your age, height and weight by using a gender-specific formula.

Step 1

Measure your height in inches. Convert the result to centimeters by multiplying by 2.54.
For example, if are you are 70 inches tall, you multiply 70 by 2.54 to get 178 cm.

Step 2

Weigh yourself on a bathroom scale. Convert your weight from pounds to kilograms by dividing by 2.2. 
For example, if you weigh 173 lb., you divide 173 by 2.2 to get 78.6 kg.

Step 3

Calculate the BMR for males in units of calories per day. The following equation provides this calculation:

 BMR = (height in centimeters x 6.25) + (weight in kilograms x 9.99) - (age x 4.92) + 5.

For example, if your height is 178 cm, your weight is 78.6 kg and your age is 37, you would use: (178 x 6.25) + (78.6 x 9.99) - (37 x 4.92) + 5 = 1,721 calories per day.

Step 4

Calculate the BMR for females in units of calories per day. The following equation provides this calculation:

 BMR = (height in centimeters x 6.25) + (weight in kilograms x 9.99) - (age x 4.92) - 161.

For example, if your height is 178 cm, your weight is 78.6 kg and your age is 33, you would use: (178 x 6.25) + (78.6 x 9.99) - (33 x 4.92) -- 161 = 1,574 calories per day.

SOURCE