Macro Calculator
Turn your calorie target into grams of carbs, protein, and fat. Choose a balanced, low-carb, or high-protein preset and watch your macro breakdown update instantly.
Your details
Your macro split
40/30/30 · C/P/FCalories tell you how much to eat; macros tell you what those calories should be made of. This macro calculator takes your daily calorie target — based on your stats and whether you're cutting, maintaining, or bulking — and divides it into the three macronutrients. Protein and carbohydrates provide 4 calories per gram; fat provides 9. Switch presets and the donut re-animates to show your new split in both grams and calories.
How macros are calculated
Each macro preset is a set of percentages that split your total calories: balanced is 40% carbs, 30% protein, 30% fat; low-carb is 20/40/40; high-protein is 30/40/30. To convert those calorie shares into grams, we divide the protein and carb calories by 4 and the fat calories by 9, since that's how much energy each gram provides.
There's no single 'best' split — the right one depends on your goal, your training, and your food preferences. Higher protein helps preserve muscle in a deficit and supports growth in a surplus, while carbs fuel intense exercise and fats support hormones.
Choosing a macro preset
The balanced 40/30/30 split is a sensible default that works for most people and most goals. Low-carb (20/40/40) suits those who feel better on fewer carbs or are managing blood-sugar responses. High-protein (30/40/30) favours anyone focused on building or keeping muscle, especially while dieting.
Whichever you pick, hitting your calorie target matters most for weight change; your macro split fine-tunes body composition, energy, and satiety on top of that.
Frequently Asked Questions
Macros, or macronutrients, are the three nutrients that provide energy: carbohydrates, protein, and fat. Carbs and protein give 4 calories per gram; fat gives 9. Your macro split determines what your calories are made of.
Start with your daily calorie target, then apply a percentage split — for example 40% carbs, 30% protein, 30% fat. Divide protein and carb calories by 4 and fat calories by 9 to get grams. This calculator does it automatically.
It depends on your goal. A balanced 40/30/30 works well for most people; low-carb (20/40/40) suits some dieters; high-protein (30/40/30) is ideal for building or preserving muscle. Total calories matter more than the exact ratio for weight change.
Most active people do well on roughly 1.6–2.2 grams of protein per kilogram of bodyweight. The high-protein and low-carb presets here push protein toward that range; for a bodyweight-based target, see our muscle-gain calculator.
For weight gain or loss, total calories are the primary driver. Macros fine-tune body composition, performance, and how full you feel — important, but secondary to hitting your calorie target.
These results are estimates for general educational purposes only and are not medical or nutritional advice. Individual needs vary. Consult a qualified healthcare professional or registered dietitian before making significant changes to your diet, especially if you are pregnant, breastfeeding, under 18, or have a medical condition.