Macro & TDEE Calculator

A macro calculator estimates how many grams of protein, carbohydrates, and fat you should eat each day based on your body stats and fitness goal. It works by first calculating your Total Daily Energy Expenditure (TDEE) — how many calories you burn daily — and then splitting those calories into the three macronutrients according to your chosen diet type and goal.

TDEE stands for Total Daily Energy Expenditure. It is the total number of calories your body burns in 24 hours, including your resting metabolism, digestion, and all physical activity. Knowing your TDEE gives you a precise calorie target: eat below it to lose fat, eat at it to maintain weight, and eat above it to build muscle.

The calculator uses the Mifflin-St Jeor equation, which peer-reviewed research identifies as the most accurate BMR formula for the general population, with a typical error margin of ±10%. However, no calculator can account for individual metabolic variation. Use the result as a starting point, track your weight for 2–3 weeks, and adjust your calories by ±100 per day based on results.

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest — essentially the energy needed to keep your heart beating, lungs breathing, and brain functioning. TDEE adds all physical activity on top of BMR. For most people, BMR accounts for 60–70% of their TDEE. You should never eat below your BMR for extended periods.

To lose weight, aim to eat 10–20% below your TDEE in total calories. A typical macro split for fat loss is 40% protein, 35% carbohydrates, and 25% fat. Prioritizing protein (at least 0.7–1g per pound of bodyweight) preserves muscle tissue while your body burns fat for energy. A 500-calorie daily deficit typically produces approximately 1 lb of fat loss per week.

Both work equally well — the calculator converts between them internally. Use whichever unit you think in. If you know your weight in kilograms and height in centimeters, use metric. If you know your weight in pounds and height in feet and inches, use imperial. The mathematical results are identical either way.

Recalculate your macros every 4–6 weeks, or whenever your body weight changes by more than 5 lbs (2.3 kg), your activity level changes significantly, or your fitness goal shifts. As you lose or gain weight, your TDEE changes, so your calorie and macro targets must be updated to keep making progress.

Both formulas estimate BMR, but were developed at different times using different population samples. The Mifflin-St Jeor equation (1990) is generally considered more accurate for modern populations and is the default in this calculator. The Harris-Benedict equation (revised 1984) tends to produce slightly higher estimates, which can lead to overestimating calorie needs. For most users, the difference is 50–100 calories per day.

Macros (macronutrients) are the three main nutrients your body uses for energy: protein, carbohydrates, and fat. Protein provides 4 calories per gram and is essential for muscle repair and growth. Carbohydrates provide 4 calories per gram and are your body's primary fuel source. Fat provides 9 calories per gram and supports hormone production, brain function, and vitamin absorption. Tracking macros gives you precise control over body composition.

Yes — this is called body recomposition, and it is most achievable for beginners, people returning after a break, or those with a significant amount of body fat to lose. It requires eating at or very near your TDEE with very high protein intake (1g per pound of bodyweight), combined with consistent resistance training. Progress is slower than dedicated bulking or cutting phases, but body composition improves simultaneously.