Know exactly how many calories your body needs — for weight loss, maintenance, or muscle gain — based on real science, not guesswork.
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Whether your goal is weight loss, muscle gain, or maintenance, everything starts with one number: how many calories your body actually needs. Our free calorie and BMR calculator gives you that number instantly, based on established clinical formulas — not guesswork.
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest just to keep you alive — breathing, circulation, cell production. Knowing your BMR is the foundation of any fitness or weight-management plan.
Your BMR is calories burned at rest. Your TDEE (Total Daily Energy Expenditure) adds your activity level on top of that — giving you the real number of calories you burn in a full day. This is the number you actually use for planning your diet.
Enter your age, sex, height, weight, and activity level. The tool uses the Mifflin-St Jeor equation — the most accurate and widely used formula recommended by nutrition professionals — to calculate your BMR and daily calorie needs.
Once you know your numbers, check your BMI Calculator or Body Fat % Calculator result in our Fitness category, stay on top of hydration with the Water Intake Calculator in Lifestyle, and if you train regularly, our Heart Rate Zones tool in Heart Health helps you train at the right intensity. Runners can also check the Running Pace Calculator to match training intensity with calorie needs.
A general rule is a 500-calorie daily deficit from your TDEE for roughly 0.5kg (1lb) of weight loss per week.
No — BMR is your resting burn rate only. Your daily calorie target should be based on TDEE, which includes your activity level.
It uses the Mifflin-St Jeor equation, considered the gold standard among calorie and BMR calculators for general population accuracy.
Not directly — the Mifflin-St Jeor formula uses age, sex, height, and weight. If you have a known high muscle mass or body fat percentage, treat the result as a solid starting estimate and adjust based on real-world results over a few weeks.