Macro Calculator
Calories say how much, macros say what: protein anchored to your body weight (the way research states it), fat for hormones, carbs for fuel — with the honest note that ±10 g is noise, not failure.
| 🥩 Protein | 120 g | 480 kcal |
| 🥑 Fat (~27%) | 72 g | 648 kcal |
| 🍚 Carbs (the rest) | 318 g | 1272 kcal |
Ranges, not commandments: protein is the anchor, fat keeps hormones happy, carbs fuel training. ±10 g on any line changes nothing that matters.
Spotted a mistake or have an idea? — errors get fixed and credited publicly.
Last reviewed: July 20, 2026 · Formulas verified by automated tests before every release.
What should my macros be?
Protein: 1.6–2.2 g per kg of body weight (the sports-nutrition consensus range). Fat: 25–30% of calories. Carbs: whatever calories remain. At 75 kg maintaining on 2,400 kcal with standard protein: 120 g protein, 72 g fat, 318 g carbs. Protein is the anchor; the other two are flexible within your calorie budget.
The split, in order of importance
protein = weight × 1.6–2.2 g/kg · fat = 25–30% of kcal · carbs = (kcal − protein×4 − fat×9) ÷ 4
The order matters more than the decimals: protein is set first and by body weight because muscle retention responds to absolute grams; fat gets a floor because hormones need it; carbs take the remainder because they're the flexible fuel. Start from your real maintenance number in the TDEE calculator — a macro split on top of a guessed calorie figure is precision theater.
Sources, assumptions and limitations
- Formula: Protein per international sports-nutrition position stands (1.6–2.2 g/kg); fat band 25–30% of energy per general dietary guidelines; 4/4/9 kcal per gram
- Assumptions: Healthy adults with standard goals; fat fixed at 27% (band midpoint) for the display; cut −20% and bulk +10% are common starting adjustments, not laws.
- Not included: Medical nutrition therapy, ketogenic or other therapeutic diets, competition prep. Educational tool, not medical advice — a registered dietitian beats any calculator.
- Last reviewed: July 29, 2026 by the CalcNotebook team
Frequently asked questions
How do I calculate my macros?
Three steps: set calories from your TDEE and goal (−20% to cut, +10% to build); anchor protein by body weight (1.6–2.2 g/kg from sports-nutrition research); give fats ~25–30% of calories; carbs get everything left. At 75 kg and 2,400 kcal maintenance: 120 g protein, 72 g fat, 318 g carbs.
Why is protein set by body weight and not percentage?
Because your muscles care about grams, not ratios. A percentage silently shrinks protein when calories drop — exactly when you need it most to keep muscle. Research (1.6–2.2 g/kg) is expressed per kilogram for that reason; percentages are for the energy macros, fat and carbs.
Do I have to hit these numbers exactly?
No — and anyone who says otherwise is selling precision that nutrition science does not have. ±10 g on any line is noise. Protein is the anchor worth tracking; fat and carbs can trade places freely within your calories depending on preference and training.
Where do I get my TDEE number?
From our TDEE calculator — it uses the clinically preferred Mifflin-St Jeor equation and honestly shows its ±10% error band. Compute it there, paste it here, and re-check against real scale trends every few weeks.