This sleeping BMR calculator estimates the daily calories that are burned while you are asleep or doing nothing for 24 hours. Read more about the basal metabolic rate and calorie burning below the form.
How does the sleeping BMR calculator work?
This useful tool can help you discover how many calories your body needs per day in order to maintain only the basic functions, this assuming that you only sleep or rest for the whole 24 hours.
In other words, the BMR calculator determines the minimum amount of energy you need to keep your vital body functions working properly. In order to provide you with this type of calculation you are going to be asked to input some data.
You will also have to decide whether you want to use the metric or the English system for your convenience.
There are then four things that you need to provide, your height, either in ft and inches or centimeters, your weight in lbs or kg and your age and gender.
The age is important to include because it reflects the way this value will decrease as one gets older. This, combined with the tendency to exercise less as we age, partly explains the tendency to put on weight as years go by.
Once you press calculate you are going to receive the value or BMR in daily calories. You can learn more about this calculation rate in the next section.
What is the basal metabolic rate?
This is defined as the amount of energy expended daily by humans or animals while they rest. This refers to what you need in order to keep your body alive with all the vital functions (for instance, but not limited to: heart beating, nervous system, skin, muscles).
It has been scientifically proved that the human body is continuously burning calories. This means that you use energy no matter what you're doing, even when you are sleeping.
Please note that your BMR estimation does not include the calories your burn while doing your daily activities or exercises, it includes only the minimum amount of energy to stay alive while resting.
There are few formulas to calculate your BMR, but below we will focus on presenting only the BMR formula we chose to use for this calculator.
English BMR Formula
■ Female: BMR = 655 + (4.35 x Weight in pounds) + (4.7 x Height in inches) - (4.7 x Age in years)
■ Male: BMR = 66 + (6.23 x Weight in pounds) + (12.7 x Height in inches) - (6.8 x Age in years)
Metric BMR Formula
■ Female: BMR = 655 + (9.6 x Weight in kg) + (1.8 x Height in cm) - (4.7 x Age in years)
■ Male: BMR = 66 + (13.7 x Weight in kg) + (5 x Height in cm) - (6.8 x Age in years)
Example BMR calculation:
For a female aged 30, weighing 165 lbs at a height of 5ft 4in.
BMR = 655 + (4.35 x 165) + (4.7 x 65) - (4.7 x 30)
The calculated BMR value is going to be: 1,533 calories/ day. You can restart the calculation with any values you want for as many times as you like by pressing Calculate again.
The BMR calculator cannot be 100% accurate because it does not take into account body fat composition.
For example, there is a big difference between a person with a heavy muscular built and another person with the same weight but with more body fat.
In the case of the muscular person the BMR value under estimates their calorie needs while for the person carrying more fat, the BMR value will over estimate calorie requirement.
It should also be taken in consideration that although the body autonomous controls the rate of metabolic energy consumption this process can be influenced by environmental factors such as stress, excitement and even temperature.
1) Harris J, Benedict F. (1918) A Biometric Study of Human Basal Metabolism. PNAS 4 (12): 370–3.
2) Müller, B; Merk, S; Bürgi, U; Diem, P. (2001) Calculating the basal metabolic rate and severe and morbid obesity. Praxis (Bern 1994) 90 (45): 1955–63.
3) Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. (1990) A new predictive equation for resting energy expenditure in healthy individuals. The American journal of clinical nutrition 51 (2): 241–7.17 Dec, 2014