Calories | Macronutrients | Lean Body Mass | Basal Metabolic Rate | More Calculators

Everybody requires a minimum number of calories to live. This minimum number is called the basal metabolic rate (BMR). Your BMR is the number of calories your organs need to function while you perform no activity whatsoever—like if you stayed in bed all day.

If you're looking to lose weight, build muscle, or maintain your weight, this information can help you calculate the number of calories you need so you can make more informed decisions about your nutrition and exercise. Use this calculator to learn your BMR and the next steps to move toward your fitness goals!

How did we calculate your BMR?

Bodybuilding.com's calculator uses the Harris-Benedict equation, which is considered by many experts to be the most accurate BMR calculation for most types of people. Here's how it works:

For men: BMR = 66.5 + (13.75 x weight in kg) + (5.003 x height in cm) - (6.755 x age in years)

For women: BMR = 655.1 + (9.563 x weight in kg) + (1.850 x height in cm) - (4.676 x age in years)

Bear in mind that this doesn't take your activity level into account!

What Is a Healthy BMR?

This will vary person by person. Since your basal metabolic rate is based largely on involuntary functions like breathing and pumping blood, changes in your day-to-day activity don't do much to raise or lower this number. However, increasing muscle mass does increase BMR, because muscle is metabolically "hungry" and it takes more energy to maintain more muscle. This means that when you have a lot of muscle mass, you'll burn more calories at rest.

The overall number of calories your body uses on a daily basis is referred to as your "total daily energy expenditure" (TDEE). It's determined based on your BMR as well as your activity level throughout the day. This varies significantly based on your activity level, age, and sex.

You can use a TDEE calculator or calorie calculator to find this number to get a more specific result. Keep in mind, though, that it's impossible to know your exact TDEE, as your activity levels will change day to day, and the only way to get 100 percent accurate BMR numbers is through laboratory testing.

What's the Difference Between BMR and RMR?

The term BMR is sometimes used synonymously with RMR, which stands for "resting metabolic rate." The difference is that while BMR only measures basic processes of breathing, blood circulation, and temperature regulation in a completely resting state, RMR also includes energy expended by digestion and non-exercise daily movements, like getting dressed and lifting your fork to your mouth.

BMR and RMR numbers are typically close enough to be interchangeable, but if you're calculating your needs in order to gain or lose weight, pay attention to which number an equation calls for. If it's based on BMR, you can use the calculator above to get an estimate. If the equation uses RMR, use our RMR calculator, which will give you a slightly higher number.

How Can I Use My BMR to Lose Fat or Gain Muscle?

Once you use your BMR to determine your TDEE, you can make sure that the nutrition plan you follow is appropriate for your level of energy expenditure and that it isn't giving you too many or too few calories. Being armed with this knowledge, rather than guesstimating or blindly following a plan without scaling it to your individual needs, can make or break your muscle gains or fat loss.