Macro Calculator

What are Macronutrients?

Macronutrients — or "macros" — are the three major nutrient classes that provide your body with energy: protein, carbohydrates, and fat. Unlike micronutrients (vitamins and minerals), which are needed in small amounts, macronutrients are required in large quantities because they are your body's primary fuel source. Every calorie you consume comes from one of these three macros.

Understanding and tracking your macronutrient intake is one of the most powerful evidence-based tools for body composition change — whether your goal is fat loss, muscle gain, or performance improvement.

How to Use This Macro Calculator

Select your gender and goal (Maintain, Cut, or Bulk), then enter your age, height, and weight. Choose your activity level and preferred diet style. Your personalised daily calorie target and macro split — including grams of protein, carbohydrates, and fat — update instantly with animated progress bars.

The Three Macronutrients Explained

Protein — 4 calories per gram

Protein is the structural building block of muscle, enzymes, hormones, and immune cells. It has the highest thermic effect of food (TEF) of all three macros — your body burns approximately 20–30% of protein calories just through digestion. Protein also promotes satiety, making it the most important macro for body recomposition. The International Society of Sports Nutrition (ISSN) recommends 1.4–2.0g of protein per kg of bodyweight for active individuals.

Carbohydrates — 4 calories per gram

Carbohydrates are your body's preferred fuel for high-intensity exercise. They are stored as glycogen in the muscles and liver, and provide the most readily available energy for anaerobic activity. Contrary to popular belief, carbohydrates are not inherently fattening — excess total calories cause fat gain, regardless of the source. The quality of carbohydrates matters: whole grains, vegetables, and fruits provide fibre and micronutrients alongside energy.

Fat — 9 calories per gram

Dietary fat is essential for hormone production (including testosterone and oestrogen), absorption of fat-soluble vitamins (A, D, E, K), brain function, and cellular membrane integrity. Fat should never be eliminated entirely from a diet. A minimum intake of approximately 0.5–1.0g per kg of bodyweight is needed to maintain hormonal health.

Diet Styles — Which Split is Right for You?

Macro Priorities by Goal

Fat Loss (Cut)

During a calorie deficit, protein becomes even more critical — it preserves lean muscle mass that would otherwise be lost alongside fat. Aim for the higher end of the protein range (1.8–2.2g/kg). Carbohydrates should be timed around workouts for performance, and fat should remain sufficient for hormonal health. Use our Calorie Deficit Calculator to set your calorie target first.

Muscle Gain (Bulk)

In a caloric surplus, protein remains the priority (1.6–2.0g/kg) and carbohydrates should be plentiful to fuel training and replenish glycogen. Fat intake can remain moderate. Quality of the surplus matters — a clean bulk of 200–300 calories above TDEE minimises unnecessary fat gain.

Maintenance

At maintenance calories, a balanced macro split supports energy, body composition stability, and health. Protein at 1.4–1.8g/kg is sufficient for most active individuals. Prioritise whole food sources across all three macros.

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