Nutrition
Macronutrient Splitter
Get daily protein, carb, and fat targets — enter a calorie target directly, or calculate one from your body stats and goal.
Last reviewed: August 2026
Result
Fill in the fields to see your result.
How this is calculated
Protein and carbohydrates provide roughly 4 kcal per gram, fat roughly 9 kcal per gram. If you calculate your calorie target here, it uses the Mifflin-St Jeor BMR equation, multiplied by your activity level to get TDEE (total daily energy expenditure), then adjusts by ±500 kcal/day for a roughly 0.5 kg/week weight change — a standard, moderate rate used in most clinical weight-management guidance.
Choosing a split
There's no single optimal macro ratio backed by strong long-term evidence for the general population — adherence and total calorie balance tend to matter more than the exact split for most health outcomes. Higher-protein splits are more commonly recommended during structured fat-loss or strength-training phases.
Worked example
Example
A 2,000 kcal/day target split 30% protein / 35% carbs / 35% fat:
- Protein: 2,000 × 0.30 = 600 kcal ÷ 4 = 150 g
- Carbs: 2,000 × 0.35 = 700 kcal ÷ 4 = 175 g
- Fat: 2,000 × 0.35 = 700 kcal ÷ 9 ≈ 78 g
Grams, not percentages, are what you'll actually track against food labels — this is why the tool converts the split for you.
Common mistakes
- Tracking percentages instead of grams. Food labels list grams; percentages are only useful for setting the split, not for daily tracking.
- Setting protein too low. Protein below roughly 1.2–1.6 g per kg of body weight makes it harder to preserve muscle during a calorie deficit, regardless of the overall split chosen.
- Chasing an "ideal" ratio instead of one you can sustain. A split you can follow consistently for months tends to outperform a theoretically optimal one you abandon after two weeks.
Why 4 kcal/gram for protein and carbs but 9 for fat?
These are the widely used Atwater general factors for the average energy yield of each macronutrient when metabolized — they've been standard in nutrition labeling for over a century.
Is a high-protein split always better for fat loss?
Higher protein tends to help with satiety and preserving lean mass during a deficit, but the primary driver of weight change is still total calorie balance, not the macro split alone.
Do I need to hit these numbers exactly every day?
No — most guidance treats these as weekly averages to aim for, not numbers that must be hit precisely every single day.
Sources
- Mifflin MD, St Jeor ST, et al. Am J Clin Nutr, 1990 (BMR basis for calorie target).
- U.S. Department of Agriculture, Atwater general factors for energy value of macronutrients.