Find your Basal Metabolic Rate and daily calorie burn (TDEE).
What is BMR? Your Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest to keep you alive — breathing, circulation, and cell repair. Knowing your BMR is the starting point for setting daily calorie targets for weight loss, maintenance, or gain.
Your BMR (at complete rest)
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TDEE (with your activity)
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Weekly burn (approx.)
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Mifflin-St Jeor equation — the most validated BMR formula.
Tip: calculate first — your result is included when you share.
📚 Related guide:BMR vs TDEE: What's the Difference? — BMR is your rest-day burn, TDEE adds movement and exercise. The formulas, activity multipliers and a worked example.
How to Use the BMR Calculator
Your BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest — just keeping you alive: breathing, blood circulation, brain activity. For most people it accounts for 60–70% of all calories burned in a day, which is why it's the foundation of every diet plan.
Enter your age, gender, height, weight and activity level, then press Calculate BMR. This tool uses the Mifflin-St Jeor equation, considered the most accurate formula for the general population. You'll get your BMR plus your TDEE (Total Daily Energy Expenditure) — BMR multiplied by your activity factor — which is the number of calories that maintains your current weight.
Once you know your TDEE, weight goals become simple maths: eat about 500 kcal less per day to lose roughly 0.5 kg per week, or 500 more to gain at a similar rate. Your BMR also explains why crash diets backfire — eating far below BMR for long periods slows your metabolism and burns muscle.
Use your TDEE as the starting point in our Calorie Calculator to set a daily target, and check body fat percentage alongside weight for the full picture.
Frequently Asked Questions
What is the difference between BMR and TDEE?
BMR is what you burn at complete rest. TDEE adds all activity — exercise, walking, work — on top of BMR. TDEE is the number that maintains your current weight.
Which BMR formula is most accurate?
Mifflin-St Jeor is the most validated for healthy adults, usually within ~10% of lab measurements. Older formulas like Harris-Benedict tend to overestimate.
Does muscle really burn more calories than fat?
Yes — muscle tissue burns roughly 3x more calories at rest than fat tissue. That's why two people at the same weight can have different BMRs.
Does BMR drop with age?
Slowly — about 1–2% per decade after 20, mostly because people lose muscle. Strength training largely offsets it.
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