Calculate your daily protein, carbs, and fat targets
Macronutrients -- commonly called "macros" -- are the three main categories of nutrients your body uses for energy: protein, carbohydrates, and fat. Each macro plays a distinct role in fuelling your body, supporting muscle growth, regulating hormones, and maintaining overall health. Tracking macros rather than just calories gives you far more control over your body composition and performance. Protein is essential for muscle repair and growth, with a typical recommendation of 1.6 to 2.2 grams per kilogram of body weight for active individuals. Carbohydrates are the body's preferred energy source, particularly for high-intensity exercise and brain function. Fats are vital for hormone production, cell membrane integrity, and absorbing fat-soluble vitamins (A, D, E, and K). The optimal ratio of protein, carbs, and fat depends on your goals. Someone focused on muscle gain typically needs higher protein and carbs, while someone following a ketogenic approach dramatically reduces carbs in favour of fats. This calculator lets you set your daily calorie target and goal, then provides a gram-level breakdown of each macronutrient based on evidence-based ratios.
To calculate your daily macros: 1. Enter your daily calorie target. If you do not know your target, use the TDEE Calculator first to determine your maintenance calories, then adjust based on your goal (surplus for muscle gain, deficit for fat loss). 2. Select your goal. "Maintain" uses a balanced macro split suitable for weight maintenance. "Lose Weight" increases the protein ratio to preserve muscle during a deficit. "Gain Muscle" increases both protein and carbs to support training and recovery. 3. Choose your diet mode. "Standard" provides a conventional macro split with a moderate amount of all three macronutrients. "Keto" dramatically reduces carbohydrates (typically under 50 grams) and increases fat intake, following ketogenic diet principles. 4. Review the results. The calculator displays grams of protein, carbs, and fat per day. The pie chart shows the calorie contribution of each macro, making it easy to visualise the balance. 5. Use these targets as a daily guide when meal prepping or logging food in a tracking app.
Macro calculations are based on the caloric density of each macronutrient: protein provides 4 calories per gram, carbohydrates provide 4 calories per gram, and fat provides 9 calories per gram. The calculator first determines the percentage of total calories allocated to each macro based on your goal and diet mode. For a standard "Maintain" goal, a common split is 30% protein, 40% carbs, and 30% fat. For "Lose Weight", protein is increased to about 35% to preserve lean mass, with carbs reduced to 35% and fat at 30%. For "Gain Muscle", protein stays high at 30%, carbs increase to 45%, and fat drops to 25%. In keto mode, the split changes dramatically: approximately 25% protein, 5% carbs, and 70% fat. This forces the body to use fat (and ketones produced from fat) as its primary fuel source rather than glucose from carbohydrates. Once the percentage split is determined, the grams are calculated: protein grams = (total calories x protein percentage) / 4. Carb grams = (total calories x carb percentage) / 4. Fat grams = (total calories x fat percentage) / 9. For example, on a 2,000 calorie "Maintain" plan: protein = (2000 x 0.30) / 4 = 150g, carbs = (2000 x 0.40) / 4 = 200g, fat = (2000 x 0.30) / 9 = 67g.
These macro targets are general guidelines based on widely accepted nutritional science. Individual needs vary based on body weight, activity level, training intensity, and medical conditions. The NHS recommends that adults get about 50g of protein per day as a minimum, but active individuals typically need significantly more. If you have specific dietary requirements or health conditions, consult a registered dietitian or your GP for personalised advice.