Macro Calculator
Calories and body weight in — protein, carbs, and fat targets out.
How this is calculated
protein = 1.8 g × kg · fat = 25% of kcal ÷ 9 · carbs = remaining kcal ÷ 4
Worked example (the defaults): 2,500 kcal at 80 kg, maintaining → protein 144 g (576 kcal), fat 69 g (625 kcal), carbs 325 g (1,299 kcal). Switch to a cut and the calories drop to 2,000: protein HOLDS at 144 g — that's the g-per-kg design doing its job — while carbs absorb most of the deficit.
Honest notes before you meal-prep
These are evidence-based defaults, not personalization: very lean or very heavy bodies warrant using goal weight instead of current weight for the protein line, endurance athletes may push carbs higher at fat's expense, and medical conditions (kidney disease especially, for protein) override calculator numbers entirely. Informational only — not medical or dietetic advice.
Frequently asked questions
How are the macros calculated?
Protein first at 1.8 g per kg of body weight (the middle of the evidence-based 1.6–2.2 range for active people), fat at 25% of calories (within the 20–35% guideline band), and carbohydrates fill whatever calories remain. Protein and carbs count 4 kcal per gram, fat 9.
Where do I get my calorie number?
From our TDEE calculator — maintenance calories for your stats and activity. Then choose the goal here: cutting subtracts 20%, bulking adds 10%. Those are the moderate defaults; aggressive cuts trade muscle and adherence for speed.
Why protein by body weight and not percentage?
Because muscle retention scales with your body, not your calorie budget. On a cut, percentage-based protein shrinks exactly when you need it most; g-per-kg holds it steady — which is why serious coaches prescribe it that way.
Do I have to hit these numbers exactly?
No — treat protein as a floor to reach, fat as a range, and carbs as the flexible remainder. Day-to-day ±10 g is noise. Consistency over weeks beats precision on any single day, and no macro split outruns a calorie total that's wrong.