Free public tool
Macro Calculator
Splits a known calorie target into protein, fat, and carbohydrate grams. Protein is set first per kg body weight, fat as a percentage floor, carbohydrate takes the remainder.
Purpose & limitations
Assumes your TDEE input is reasonably accurate. Macro splits are preference-tolerant; adherence beats precision for most goals.
Inputs & validated ranges
| Input | Unit | Accepted range |
|---|---|---|
| Daily calorie target | kcal | 1000–6000 |
| Body weight | kg | 30–250 |
| Protein target | g/kg | 0.8–2.6 |
| Fat share of calories | % | 15–45 |
Formula & methodology
Protein g = weight × g/kg (4 kcal/g). Fat g = (calories × fat%) ÷ 9. Carbohydrate g = remaining calories ÷ 4.
Worked example
2700 kcal, 80 kg, 1.8 g/kg protein, 25% fat: protein 144 g (576 kcal); fat 675 kcal ÷ 9 = 75 g; carbs (2700 − 576 − 675) ÷ 4 ≈ 362 g.
References
- Thomas DT, Erdman KA, Burke LM (2016). Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. Journal of the Academy of Nutrition and Dietetics. SourcePosition stand
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