Basal Metabolic Rate, abbreviated as BMR, is the rate at which the human body burns calories while at rest.

The calculator below will quickly estimate your BMR. Simply select male / female, enter your age, weight and height (metric inputs are available), then click ‘Calculate BMR’.

Voila! Your basal metabolic rate is instantly calculated. In addition, based on your estimated activity level, the number of calories that you need to consume to maintain your current weight is displayed.

As referenced above our free online BMR calculator, your basal metabolic rate estimates how many calories your body burns while at rest.

The state of rest engulfs several different conditions. For example, the body constantly needs to maintain an internal body temperature because humans are warm blooded and keep a body temperature of about ninety-eight degrees Fahrenheit.

In order to do this, the body needs energy, and it gets that energy from calories that are consumed everyday. Other normal activities like pumping blood throughout the body and repairing cells also burns a certain number of calories.

BMR decreases with reduction of a person’s lean body mass. Generally, a person’s BMR decreases with age because people typically do not maintain lean body mass as they get older. Conversely, increasing one’s muscle mass will also appropriately increase his or her BMR.

A very specific and restrictive set of circumstances is required to make a precise measurement of an individual’s BMR during a person’s waking hours. In order to obtain an accurate Basal Metabolic Rate measurement, the person’s sympathetic nervous system needs to be not stimulated; in other words, the person needs to be at complete rest.

However, a more general estimate of a person’s BMR can be made using an individual’s gender, height, weight and age, as discussed on the BMR formula page. A calculator incorporating these variables, and based on the Harris Benedict Equation, is available for free at the top of this page.

An individual’s age, gender, weight, height, muscle mass, and body size all impact the BMR. For example, if you are tall and lean, you have a higher BMR than someone who is just as lean but shorter.

There are several conditions that can lower your BMR. These conditions include high levels of stress in day-to-day life, fasting, malnutrition, and large changes in the environmental temperature.

Fasting or beginning an extreme low calorie diet lowers an individual’s BMR dramatically. This makes it harder to lose weight while on these types of diets. However, aerobic exercise and weight training are both beneficial to one’s BMR.

If interested, we have also provided a Body Mass Index / BMI calculator, detailed BMI definition, and BMI calculation formulas on this site.