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Macro Calculator
Enter your stats and get your exact daily protein, carbs & fat targets in seconds — based on the Mifflin-St Jeor formula, the gold standard used by dietitians.
Biological Sex
Age
Weight
Height
Activity Level
Your Goal
What Are Macros?
Macronutrients are the three nutrients your body needs in large quantities. Each plays a distinct role in body composition, energy, and performance.
Protein
4 kcal/g
Builds and repairs muscle, keeps you full, and has the highest thermic effect — your body burns more calories digesting it.
Carbohydrates
4 kcal/g
Your body's preferred fuel for high-intensity training. Replenishes glycogen, supports thyroid function, and steadies mood and focus.
Fat
9 kcal/g
Essential for hormone production, fat-soluble vitamin absorption (A, D, E, K), and joint health. Healthy fats support fat loss, not hinder it.
How the Calculator Works
BMR
Mifflin-St Jeor equation: 10×weight + 6.25×height − 5×age ± gender offset. How many calories your body burns at complete rest.
TDEE
BMR × activity multiplier (1.2 to 1.9). Your Total Daily Energy Expenditure — what you actually burn each day.
Target
Fat loss = TDEE − 400 kcal. Muscle gain = TDEE + 300 kcal. Maintenance = TDEE. All scientifically validated adjustments.
Macros
Protein: 2.0–2.2 g/kg bodyweight. Fat: 25% of target calories. Carbs: whatever calories remain after protein and fat.
Common Questions
What are macros?
Macros (macronutrients) are the three main nutrients that provide calories: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). Tracking macros gives you precise control over body composition — far more effective than simply counting calories alone.
How does the macro calculator work?
The calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR), multiplies it by your activity level to get your TDEE, then adjusts for your goal. Protein is set at 1.6–2.2g per kg of bodyweight, fat at 25% of calories, and carbs fill the remainder.
How much protein should I eat per day?
For fat loss: 2.0g per kg of bodyweight. For muscle gain: 2.2g per kg. For maintenance: 1.6g per kg. These ranges are supported by peer-reviewed research and optimal for preserving or building muscle mass.
Is tracking macros better than calories?
Yes, for body composition goals. Tracking macros ensures adequate protein (preserves muscle), appropriate carbs (fuels training), and healthy fats (supports hormones). Pure calorie counting can result in muscle loss even when the scale drops.
Do I need to track macros every day?
For the first 4–6 weeks, yes — daily tracking builds awareness of portion sizes and food composition. After that, many people can intuitively maintain their targets without strict logging. Weekly averages matter more than daily perfection.
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Done Calculating?
Find Recipes Matched to Your Macros
Browse free recipes with full macro breakdowns to hit your targets.
Browse Free RecipesMethod: Mifflin-St Jeor for calories, protein per kg of bodyweight by goal (Morton et al., Br J Sports Med 2018), fat at 25% of intake. See full methodology and limitations. Estimates for general education, not medical advice.