TDEE Calculator, Daily Calorie Needs
Calculate your Total Daily Energy Expenditure, the calories you burn each day based on your body and activity level.
TDEE is the foundation of any nutrition plan. Get this number right and every other calculation, deficit for fat loss, surplus for muscle gain, maintenance for body recomposition, builds on it. The Mifflin-St Jeor equation is the most validated formula for most adults, and the activity multiplier is where most people make the biggest error by overestimating how active they actually are.
Most people overestimate their activity level. "Lightly active" means 1–3 genuine workout sessions per week, not a physically demanding job. A sedentary desk worker who runs 3x/week is lightly active at best. Overestimating adds hundreds of phantom calories to your maintenance estimate.
BMR vs TDEE
Basal Metabolic Rate (BMR) is the calories your body burns at complete rest, the energy required for breathing, circulation, cell repair, and basic organ function. It represents 60–70% of total daily energy expenditure for most people. TDEE multiplies BMR by an activity factor to account for movement and exercise. The activity multipliers (1.2–1.9) cover the full range from bed-ridden to elite athlete.
The Mifflin-St Jeor equation
For men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5. For women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161. A 2005 review comparing BMR equations found Mifflin-St Jeor to be the most accurate for predicting RMR in both obese and non-obese adults. The Harris-Benedict equation (older) tends to overestimate by 5–15%.
Using TDEE for fat loss and muscle gain
Fat loss: create a calorie deficit of 300–500 calories below TDEE. A 500-calorie daily deficit produces approximately 1 pound of fat loss per week. Muscle gain: eat a 200–400 calorie surplus above TDEE. Larger surpluses accelerate fat gain without meaningfully accelerating muscle gain. Body recomposition (simultaneous fat loss and muscle gain) is possible at maintenance calories for beginners and returning trainees.
Frequently asked questions
Why isn't my weight changing at my calculated TDEE?
The most common reasons: food tracking underestimates actual intake (studies show 20–40% underestimation is typical), activity multiplier is too high, or metabolic adaptation to a prolonged deficit has lowered actual TDEE. Track weight over 2–3 weeks and adjust intake based on actual results rather than calculated estimates.
Does TDEE change as you lose weight?
Yes, a lighter body burns fewer calories. Recalculate TDEE every 10–15 pounds of body weight change. Beyond the expected reduction from lower body weight, metabolic adaptation (adaptive thermogenesis) can reduce TDEE further, the body becomes more efficient in a sustained deficit.