BMR Calculator
Calculate your Basal Metabolic Rate — the calories your body burns at complete rest.
| Activity Level | Multiplier | TDEE (kcal/day) |
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Mifflin-St Jeor is the most accurate formula for most people. Harris-Benedict tends to overestimate by ~5%.
BMR formulas explained
Two formulas are widely used to estimate BMR. Both use weight, height, age and gender.
Frequently asked questions
What is BMR and why does it matter?
Basal Metabolic Rate is the number of calories your body needs to sustain basic life functions — breathing, circulation, organ function — while completely at rest. It accounts for 60–75% of total daily energy expenditure. Knowing your BMR helps you set an accurate calorie target for weight management.
What is the difference between BMR and TDEE?
BMR is the calorie burn at complete rest. TDEE (Total Daily Energy Expenditure) multiplies BMR by an activity factor to estimate total calories burned in a day including physical activity. For weight loss you should consume fewer calories than your TDEE; for muscle gain, more.
Which formula is more accurate — Mifflin-St Jeor or Harris-Benedict?
A 2005 meta-analysis found Mifflin-St Jeor to be the most accurate for the general population, predicting BMR within 10% for about 82% of subjects. Harris-Benedict tends to overestimate by 5% or more, especially for overweight individuals. Use Mifflin-St Jeor as your primary estimate.
Does BMR change with age?
Yes. BMR typically declines about 1–2% per decade after age 20, primarily due to loss of muscle mass (sarcopenia). Strength training can slow this decline by preserving muscle tissue. Women also experience a notable drop around menopause.
How accurate are activity multipliers for Indians?
Activity multipliers are population estimates and may not reflect individual variation. Many urban Indians have desk jobs (sedentary ×1.2) but may walk significantly during commutes. Tracking actual calorie expenditure with a fitness watch gives a more personalised TDEE estimate.