Macro Calculator

Enter your daily calorie target and goal to get your personalised macro split — grams of protein, carbohydrates, and fat to hit every day.

kcal

Don't know your TDEE? Use our TDEE Calculator first.

Numbers shown: Protein % / Fat % / Carbs %

What Are Macronutrients?

Macronutrients — commonly called "macros" — are the three major categories of nutrients that provide energy: protein, carbohydrates, and fat. Protein provides 4 calories per gram and is the primary building block for muscle, enzymes, and hormones. Carbohydrates provide 4 calories per gram and are the body's preferred energy source, especially during high-intensity exercise. Fat provides 9 calories per gram and is essential for hormone production, fat-soluble vitamin absorption, and cell membrane integrity.

Unlike micronutrients (vitamins and minerals), which are required in trace amounts, macronutrients are consumed in large quantities every day. Your unique macro needs depend on your total calorie intake, body composition goals, and activity level — which is why a personalised approach produces far better results than generic advice.

Why Do Macros Matter?

Total calories determine whether you gain or lose weight, but your macro split determines what type of tissue you gain or lose. Two people on the same calorie deficit can have very different outcomes — one losing fat while preserving muscle, the other losing both — depending entirely on their protein intake. Similarly, for muscle gain, surplus calories from protein and carbohydrates support muscle protein synthesis far more effectively than an equivalent surplus from fat alone.

Start by calculating your Total Daily Energy Expenditure with our TDEE Calculator to establish your calorie baseline, then use this macro calculator to distribute those calories into the most effective split for your goal.

How to Calculate Your Macros

The starting point is your TDEE — the total calories you need each day to maintain your current weight. From there, adjust up or down based on your goal (surplus for muscle gain, deficit for fat loss), then split the calories across the three macros using goal-appropriate percentages. For example, at 2,500 kcal with a muscle gain goal (30 / 25 / 45 split): protein = 750 kcal ÷ 4 = 188 g; fat = 625 kcal ÷ 9 = 69 g; carbs = 1,125 kcal ÷ 4 = 281 g. For individual protein targets, use our Protein Calculator.

Macros for Muscle Gain

For muscle gain, a 30 / 25 / 45 split (protein / fat / carbs) is a widely used and evidence-backed starting point. The 30% protein allocation ensures adequate amino acids for muscle protein synthesis, while the 45% carbohydrate allocation fuels training and replenishes muscle glycogen. Fat at 25% maintains hormonal health. This split should be applied to a calorie surplus of approximately 200–400 kcal above your TDEE to support lean muscle growth without excessive fat gain.

Macros for Weight Loss

For weight loss, a higher protein percentage (35%) helps preserve lean muscle mass during a caloric deficit. Carbohydrates are reduced to 35%, and fat is maintained at 30% to support satiety and hormonal function. The deficit should be 300–500 kcal below TDEE for sustainable fat loss of approximately 0.5–1 kg per week. The higher protein intake at this split also increases the thermic effect of food, further supporting the calorie deficit.

What Is a Keto Macro Split?

The ketogenic (keto) diet uses an extreme macro split — approximately 30% protein, 65% fat, and just 5% carbohydrates — to induce a metabolic state called ketosis. In ketosis, the body switches its primary fuel source from glucose (from carbs) to ketone bodies (from fat), which requires restricting carbohydrates to roughly 20–50 g per day. While keto can be effective for weight loss and blood sugar management in some individuals, it is not suitable for everyone and requires careful planning to avoid nutrient deficiencies. Consult a healthcare provider before starting a ketogenic diet. Use our BMR Calculator to establish your calorie baseline before adjusting your macro ratios.

Scientific References: Institute of Medicine. (2005). Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. National Academies Press. — Helms ER, et al. (2014). A systematic review of dietary protein during caloric restriction in resistance trained lean athletes. J Int Soc Sports Nutr. 11:20.

Medical Disclaimer: The results provided by this calculator are for informational and educational purposes only. They are not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider or registered dietitian before making significant changes to your diet or exercise plan.

Last reviewed: July 2026 · Based on current WHO & ACSM guidelines.

Frequently Asked Questions

What are macros in nutrition?

Macros (macronutrients) are the three main nutrient categories that provide calories: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). They form the bulk of your daily calorie intake and each plays a distinct role in energy production, muscle building, hormone regulation, and overall health.

How do I track my macros?

The most practical way to track macros is using a food logging app such as MyFitnessPal or Cronometer. You enter the foods you eat, and the app calculates your macro intake from a nutrition database. Weigh your food with a kitchen scale for accuracy, especially when starting out. Most people find that after 4–8 weeks, they develop a reliable intuitive sense of the macro content in their regular meals.

What is the best macro split for weight loss?

For weight loss, a split of approximately 35% protein, 30% fat, and 35% carbohydrates works well for most people. The high protein percentage preserves muscle mass during the deficit, increases satiety, and has a higher thermic effect than other macros. The exact split is less important than being in a consistent calorie deficit — so choose ratios you can sustain long-term.

How many carbs per day?

Carbohydrate needs vary greatly by activity level. For a sedentary person on a 2,000 kcal diet, a maintenance split allocates about 225 g of carbs per day. For an endurance athlete training 10+ hours per week, 400–600 g is common. On a ketogenic diet, carbs are restricted to 20–50 g per day. There is no universally "correct" amount — it depends on your calorie target, goal, and activity level.

What percentage of calories should come from fat?

For most health and fitness goals, 20±35% of total calories from fat is a well-supported range. Fat is essential for hormone production (particularly testosterone and oestrogen), fat-soluble vitamin absorption (A, D, E, K), and cell membrane function. Dropping below 20% of calories from fat is generally not recommended for long periods. The exception is the ketogenic diet, where fat is deliberately elevated to 60±70%.

Do I need to count macros to lose weight?

No — you can lose weight without tracking macros as long as you maintain a consistent calorie deficit. However, tracking macros (particularly protein) significantly improves body composition outcomes. People who track protein intake tend to preserve more muscle during weight loss and achieve better body recomposition results than those who only track calories. You don't need to track forever — even 4–8 weeks of precise tracking builds lasting intuitive awareness of macro content.