Free Tool · Nutrition
Calorie & Macro Calculator
Get precise daily calorie and macronutrient targets using the Mifflin-St Jeor equation, validated against every major body composition study since 1990. Enter your details below. No account, no email, no spam.
How it works
Four numbers, calibrated to you
Daily energy expenditure is the sum of four components. Your Basal Metabolic Rate (BMR) covers baseline survival functions. Thermic Effect of Feeding (TEF) is the energy required to digest what you eat. Exercise Energy Expenditure (EEE) captures structured training. Non-Exercise Activity Thermogenesis (NEAT) covers everything else you do while awake.
Add these together and you get Total Daily Energy Expenditure (TDEE). Your calorie target is TDEE plus or minus a deficit or surplus, depending on whether you want to lose, maintain, or gain weight. We apply a surplus or deficit between 250 and 1000 calories per day, capped to stay within safe rates of change.
Formulas we use
Research-grade equations
Mifflin-St Jeor for BMR: the predictive equation recommended by the Academy of Nutrition and Dietetics for healthy adults. It outperforms older formulas like Harris-Benedict by roughly 5 percent on average and is the basis for most modern nutrition software.
Protein targets scale with training goal. Strength and hypertrophy goals get 0.9 to 1.0 grams per pound of bodyweight. Endurance goals get 0.7 grams per pound. These ranges are drawn from the International Society of Sports Nutrition position stand on protein.
Fat targets are set as a percentage of total calories to protect hormonal health, with carbohydrates filling the remaining calorie budget.
Frequently asked questions
Questions we hear a lot
Basal Metabolic Rate is the number of calories your body needs at complete rest to keep essential systems running. We use the Mifflin-St Jeor equation, the most accurate predictive formula for healthy adults and the standard recommended by the Academy of Nutrition and Dietetics.
Mifflin-St Jeor predicts resting metabolic rate within about 10 percent of measured values for most people. It outperforms older formulas like Harris-Benedict for the general population. Individual variation exists, so use the output as a starting point and adjust based on real-world results over two to four weeks.
Yes. Your BMR and TDEE scale with body mass, so every 10 pounds of change materially shifts your targets. Recalculate after any 10-pound change or every 4 to 6 weeks during an active cut or bulk.
Protein is set based on bodyweight and your training goal (higher for strength and hypertrophy, moderate for endurance). Fat is set as a percentage of total calories for hormonal health. Carbohydrates fill the remaining calorie budget, which means they scale up with training volume and down during fat loss.
Yes. The Sculpt AI calorie and macro calculator is free and requires no account. For continuous adaptive nutrition plans that update with your progress, the Sculpt AI app provides deeper tracking on iOS.
Yes. Select a weight-loss goal to apply a calorie deficit ranging from 250 to 1000 calories per day. A 500-calorie daily deficit produces roughly 1 pound of fat loss per week for most people, assuming compliance and adequate protein intake.