Macro Calculator
Calculate your ideal daily macronutrient breakdown — protein, carbohydrates, and fat — tailored to your body weight, calorie target, and goal (cut, maintain, bulk, or keto).
Frequently Asked Questions
What are macros and why do they matter?
Macronutrients (macros) are the three main dietary energy sources: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). Total calorie intake controls weight gain or loss, but the macro split determines body composition — how much of that weight change is fat vs. muscle. High protein preserves muscle during a cut; sufficient carbohydrates fuel performance; adequate fat supports hormones. Tracking macros is more precise than just counting calories.
How much protein do I need per day?
The evidence-based range for muscle building and preservation is 1.6–2.2 g of protein per kg of bodyweight per day (0.73–1.0 g/lb). Aim for the higher end during a calorie deficit or if over age 40 to counteract muscle-protein breakdown. A 75 kg person needs roughly 120–165 g of protein daily. Spreading protein over 3–5 meals of 30–40 g maximises muscle protein synthesis (the leucine threshold per meal). Whey, chicken, fish, eggs, and Greek yogurt are high-quality sources.
What is the best macro split for fat loss (cutting)?
For cutting, a common evidence-based split is: Protein 30–35% of calories (high, to preserve muscle), Fat 25–35% (for hormones and satiety), Carbohydrates 35–45% (fuels training). Example for 1,800 kcal: ~155 g protein, ~60 g fat, ~185 g carbs. Adjust carbs and fat to personal preference — some people perform better on higher carbs for gym sessions; others prefer more fat and fewer carbs. Protein should remain non-negotiable.
What is the best macro split for muscle building (bulking)?
For bulking: Protein 25–30% of calories, Carbohydrates 45–55% (glycogen fuels training, supports anabolism), Fat 20–30%. Example for 3,000 kcal: ~185 g protein, ~375 g carbs, ~75 g fat. Carbohydrates are prioritised because they replenish muscle glycogen, support insulin-mediated nutrient delivery, and power high-volume workouts. Protein above 2.2 g/kg shows diminishing returns in trained individuals.
What is a ketogenic macro split and who is it suited for?
Keto limits carbohydrates to under 50 g/day (~5% of calories), with fat at 65–75% and protein at 20–30%. This forces the body into ketosis — producing ketones from fat as the primary fuel source. Keto can be effective for fat loss and may benefit people with type 2 diabetes, epilepsy, or metabolic syndrome. Downsides: adaptation takes 2–4 weeks (keto flu), it can impair high-intensity athletic performance due to reduced glycogen availability, and requires strict adherence.