TDEE Calculator

About this calculator

TDEE (Total Daily Energy Expenditure) is an estimate of how many calories your body burns each day. It combines your Basal Metabolic Rate (BMR), the energy cost of keeping basic physiology running at rest, with a multiplier that accounts for physical activity.

This calculator implements two validated equations. When no body-fat percentage is entered, it uses the Mifflin-St Jeor equation (Mifflin MD et al., Am J Clin Nutr. 1990;51(2):241-247), which was validated in 498 adults against measured resting energy expenditure and outperformed older equations like Harris-Benedict. When body-fat percentage is provided, it switches to the Katch-McArdle equation (McArdle WD, Katch FI, Katch VL. Exercise Physiology. 3rd ed. 1991), which uses lean body mass directly and is more accurate for individuals with known body composition data.

Activity multipliers are Physical Activity Level (PAL) coefficients from the Institute of Medicine Dietary Reference Intakes (2002, NBK222888): sedentary 1.2, light 1.375, moderate 1.55, very active 1.725, extra active 1.9.

Macro targets follow the International Society of Sports Nutrition position stand on protein and exercise (Stokes T et al., Nutrients. 2018;10(2):180): 1.6-2.0 g/kg lean body mass depending on goal, fat at approximately 27.5% of calories, carbohydrates filling the remainder.

BMR equations are population-level estimates with an individual variance of roughly 10% in either direction. Activity factors are heuristics, not measurements. Use these numbers as an informed starting point and refine your intake based on 2-4 weeks of body-weight trend data.

This tool is for educational and planning purposes only. It does not constitute medical or dietetic advice. Consult a licensed physician or registered dietitian before making significant changes to your nutrition.