BMR Calculator
Find your estimated Basal Metabolic Rate and daily calorie needs in a few simple steps.
This estimate includes your selected activity level.
What is BMR?
BMR stands for Basal Metabolic Rate. It is the estimated amount of energy your body uses at rest to maintain essential functions such as breathing, circulation, and keeping your body temperature stable. Even when you are resting, your body continues to use energy to keep important organs and systems working.
Your BMR is influenced by several factors, including age, sex, height, weight, and body composition. In general, body size and muscle mass can have a significant effect on how much energy the body uses at rest. BMR also tends to change as a person gets older.
How is BMR calculated?
This calculator uses the Mifflin–St Jeor equation, a commonly used formula for estimating resting energy requirements in adults. The calculation uses your age, sex, height, and weight to produce an estimated number of calories your body may require each day at rest.
The result is an estimate rather than a direct measurement. Actual energy expenditure can vary from person to person because metabolism is affected by factors such as body composition, physical activity, health conditions, medications, sleep, and other individual differences.
BMR and daily calorie needs
BMR is not the same as the number of calories you normally need in a day. Your body uses additional energy when you walk, work, exercise, digest food, and perform everyday activities.
For this reason, the calculator also provides an estimated daily calorie requirement based on the activity level you select. This is often referred to as Total Daily Energy Expenditure, or TDEE. It gives a broader estimate of your daily energy needs than BMR alone.
Why should you use a BMR calculator?
A BMR calculator can be useful when you want a starting point for understanding your energy requirements. It may be helpful when planning general nutrition, exercise, or weight-management goals.
However, one number should not be used on its own to make decisions about your health. Your calorie requirements can change over time, and estimated formulas cannot account for every individual factor.