Macros Calculator
Split your daily calories into protein, carbs, and fat.
Enter your calories to see your macros
Your daily protein, carbs, and fat — in grams and percentages, with preset splits to compare.
How to use this calculator
- 1
Enter your daily calories
Your daily calorie target. Don't know it? Calculate your TDEE first — that gives you maintenance, and you can adjust from there.
- 2
Pick a split
Balanced, High protein, Low carb, or Keto. All sit within the IOM's AMDR ranges except keto (which is intentionally outside).
- 3
Read your results
Grams, calories, and percentage for protein, carbs, and fat. Click any split in the comparison list to see how the numbers shift.
What are macros?
Macros — short for macronutrients — are the three nutrients your body needs in large amounts: protein, carbohydrates, and fat. Each provides energy (calories) but plays a different role in the body.
While total calories drive weight change, the split between macros influences body composition, satiety, performance, and how your diet feels day to day.
The three macros
- Protein (4 kcal/g) — builds and repairs muscle, makes enzymes and hormones. Highest satiety per calorie. Most active adults do well with 1.6–2.2 g per kg of bodyweight per day.
- Carbohydrates (4 kcal/g) — primary fuel for high-intensity exercise and the brain. Includes sugars, starches, and fibre.
- Fat (9 kcal/g) — essential for hormones, vitamin absorption, and cell membranes. More than twice the calories per gram of protein or carbs.
Which split should I use?
No single split is "best." The right one depends on your goal, training style, food preferences, and what you can stick to. Here's how the four supported splits compare:
Balanced (30 / 40 / 30)
Default starting point. Good for general fitness, body recomposition, most people most of the time.
High protein (40 / 30 / 30)
Favoured for fat loss and lean-muscle retention. Higher protein helps with satiety in a deficit and protects muscle mass.
Low carb (30 / 20 / 50)
Higher fat, moderate carbs. Some people find this more satiating; useful if you prefer fewer/larger meals.
Keto (25 / 5 / 70)
Very low carb, intended to induce ketosis. A specific dietary protocol — not a general default. Outside the IOM AMDR by design.
In practice
Calories drive weight change; macros influence body composition, performance, and how the diet feels. If two splits give similar results, pick the one you can stick with.
Frequently asked questions
Sources & references
Guidelines and research behind the macro splits.
- Institute of Medicine (2005). Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. NIH Bookshelf
- Morton RW et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med 52(6):376–384. PubMed
- ISSN Position Stand (2017). Jäger R et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr 14:20. PubMed
Related calculators
TDEE Calculator
Total Daily Energy Expenditure — calories your body burns each day, including activity.
Open calculatorHydration Calculator
Daily water intake target adjusted for bodyweight and activity.
Open calculatorBMR Calculator
Basal Metabolic Rate — calories your body burns at complete rest.
Open calculator