Macro Calculator
Calculate your daily calories and macronutrient targets (protein, carbs, and fat) from your body metrics, activity level, and goal.
How it works
How macros are calculated
BMR = 10×kg + 6.25×cm − 5×age + s (s = +5 male, −161 female) TDEE = BMR × activity factor Calories = TDEE × (1 + goal adjustment) Protein & carbs = 4 kcal/g, fat = 9 kcal/g
First the Mifflin-St Jeor equation estimates your basal metabolic rate — the energy you burn at rest. Multiplying by an activity factor gives total daily energy expenditure (TDEE), your maintenance calories. A goal adjustment sets your target calories, which are then divided among protein, carbohydrates, and fat by your chosen split.
Worked example
A 30-year-old man, 178 cm and 75 kg, moderately active and maintaining weight, has a BMR of about 1,718 kcal and a TDEE of about 2,662 kcal. On a balanced 30/40/30 split that's roughly 200 g protein, 266 g carbs, and 89 g fat.
Frequently asked questions
What are macronutrients?
Protein, carbohydrates, and fat — the three nutrients that supply calories. Protein and carbs provide 4 calories per gram; fat provides 9. Balancing them supports your energy, muscle, and overall goals.
Which macro split should I choose?
A balanced split works for most people. Higher protein helps preserve muscle when losing weight; lower-carb or keto splits suit some people's preferences and energy patterns. There's no single best split — consistency matters more.
How accurate is the calorie estimate?
The Mifflin-St Jeor equation is one of the more accurate formulas, but any estimate can be off by 10% or more for an individual. Track your weight for 2–3 weeks and adjust calories up or down based on the trend.