BMR Calculator

Your BMR (Basal Metabolic Rate) is the energy your body needs just to keep you alive — heartbeat, breathing, brain function — before a single step or workout. It’s the foundation every calorie plan is built on.

Your basal metabolic rate
—
calories per day at complete rest

BMR is typically 60–70% of total daily burn. Add activity with our TDEE calculator.

The Mifflin-St Jeor equation

Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161

BMR vs TDEE

BMR covers only your at-rest burn. Real life adds movement, exercise, and digestion (the thermic effect of food), which is why your TDEE — the number that actually governs weight change — is always higher.

Can you raise your BMR?

Modestly. More muscle mass nudges it up (muscle burns ~6 kcal/lb/day at rest), and BMR drifts down with age and weight loss. Crash dieting can suppress it temporarily — another reason to favor moderate deficits.

Frequently asked questions

What is BMR?

Basal Metabolic Rate: the calories your body burns at complete rest to run vital functions like breathing, circulation, and cell repair.

What’s the difference between BMR and TDEE?

BMR is rest-only burn; TDEE adds all activity and exercise. TDEE is the number that determines weight loss or gain.

Does muscle really boost metabolism?

Yes, but less than myth suggests — roughly 6 calories per pound of muscle per day at rest. Ten pounds of new muscle adds ~60 kcal/day.

Why does BMR drop with age?

Mostly due to gradual muscle loss (sarcopenia) and reduced activity. Resistance training largely offsets it.

Can I eat below my BMR?

Regularly eating below BMR is hard to sustain and risks muscle loss and nutrient gaps. Most successful cuts sit between BMR and TDEE.