BMR & TDEE Calculator

The BMR and TDEE Calculator computes two foundational values for nutrition planning. Basal Metabolic Rate (BMR) is the calories your body burns at complete rest to sustain vital functions — breathing, circulation, temperature regulation and cell repair. Total Daily Energy Expenditure (TDEE) multiplies BMR by an activity factor to estimate total daily calorie burn including all movement. TDEE is the true baseline for any weight management plan: eating below TDEE leads to weight loss, above it leads to weight gain.

The Mifflin-St Jeor equation (validated 1990) is the most accurate BMR formula for most adults. Men: (10 x kg) + (6.25 x cm) - (5 x age) + 5. Women: (10 x kg) + (6.25 x cm) - (5 x age) - 161. TDEE activity multipliers: Sedentary (desk job) = BMR x 1.2; Lightly active (1-3 days exercise) = BMR x 1.375; Moderately active (3-5 days) = BMR x 1.55; Very active (6-7 days) = BMR x 1.725. For sustainable weight loss, maintain a deficit of 300 to 500 calories below TDEE. Deficits above 1,000 calories daily risk muscle loss and metabolic adaptation.

TDEE estimates carry a 10 to 15 percent margin of error — calibrate by tracking actual weight change over 2 to 3 weeks. Pair with our BMI Calculator to assess weight status and our Step Counter to track activity calories. Free, no registration required.