BMR Calculator
Calculate your Basal Metabolic Rate — the calories you burn at rest.
About you
Your BMR
1,649
calories/day at rest
Maintenance calories
2,556
Moderately active · ×1.55
Daily calories by activity level
BMR is the energy your body uses at complete rest. Multiply it by an activity factor to estimate the calories you burn in a day (TDEE). Figures are estimates from the Mifflin-St Jeor equation.
About the BMR Calculator
Your Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest just to keep you alive — powering your heart, brain, lungs and other organs. It typically accounts for 60–70% of the calories you use each day, which makes it the foundation of any calorie plan, whether you want to lose, maintain or gain weight.
This calculator uses the Mifflin-St Jeor equation, the formula most dietitians consider the most accurate for the general population. It factors in your weight, height, age and sex. To estimate the calories you actually burn in a day (your TDEE, or maintenance calories), multiply your BMR by an activity factor — the table shows all five levels so you can pick the one that matches your lifestyle.
Once you know your maintenance number, eating below it tends to lead to weight loss and above it to weight gain — roughly 3,500 calories per pound of body weight.
Frequently asked questions
What's the difference between BMR and TDEE?
BMR is the calories you burn at rest. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor — the total you burn including movement and exercise. The activity table on this page shows your TDEE at each level.
Which formula does this use?
The Mifflin-St Jeor equation, widely regarded as the most accurate BMR formula for most people. For men: 10×weight(kg) + 6.25×height(cm) − 5×age + 5; for women the final constant is −161 instead of +5.
How do I use my BMR to lose weight?
Find your maintenance calories (BMR × activity factor), then eat below it to lose weight. A deficit of roughly 500 calories a day is a common, sustainable target for about a pound of loss per week — but consult a professional for personalised advice.
Why does BMR fall with age?
Metabolism tends to slow as we age, partly due to muscle loss. The formula reflects this by subtracting more for older ages, so an older person generally has a lower BMR than a younger person of the same size.
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