Macro Calculator

What are macros and why do they matter?

Macronutrients — protein, carbohydrates, and fat — are the three categories of nutrients that provide calories. Each gram of protein and carbohydrate delivers 4 kcal, while each gram of fat delivers 9 kcal. Tracking macros lets you control not just how many calories you eat, but what those calories are made of — which directly affects body composition, energy levels, and training performance.

The calculator uses the Mifflin-St Jeor formula — the most validated method for estimating basal metabolic rate — multiplies it by an activity factor, and then distributes the resulting calorie target across the three macros based on your goal. Protein is set first (the most important macro), fat is held to a safe minimum, and carbohydrates fill the remaining calories.

Macros by goal

During fat loss, protein is set high (2.0–2.2 g/kg) to preserve muscle in a calorie deficit. Fat is kept at the minimum healthy level to free up more calories for carbohydrates, which fuel training. During muscle gain, a small calorie surplus (10–20 %) supports growth without excessive fat accumulation, and a moderate protein target (1.8–2.0 g/kg) is sufficient.

You do not need to hit your macros exactly every day. Research consistently shows that weekly averages matter more than daily precision. A ±10 % daily variation will not noticeably affect your results — consistency over weeks and months is what drives change.