How this Tool Works

A macro calculator is an essential tool for anyone serious about fitness. It moves beyond simple calorie counting to determine the quality of calories you consume. By balancing your intake of proteins, carbohydrates, and fats, you can optimize your body’s ability to burn fat or build muscle.

Calculating BMR and TDEE

First, we determine your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, widely considered the most accurate standard for estimating caloric needs. We then apply an activity multiplier to find your TDEE (Total Daily Energy Expenditure).

$$BMR = 10 \cdot weight(kg) + 6.25 \cdot height(cm) – 5 \cdot age(y) + s$$
Where ‘s’ is +5 for males and -161 for females.

Why calculate your macros?

While calories determine weight direction (up or down), macros determine body composition.

• Protein (4 cal/g): Essential for muscle repair and growth. High protein diets are often recommended by the USDA and fitness experts for satiety.
• Carbohydrates (4 cal/g): The body’s primary energy source for high-intensity training.
• Fats (9 cal/g): Vital for hormonal health and nutrient absorption.

This calculator uses a standard “Body Composition” split (30% Protein, 40% Carbs, 30% Fats) to provide a balanced starting point for most users.

Frequently Asked Questions