Body Recomposition Calculator: Calories & Protein
Get your maintenance calories and a daily protein target for building muscle while losing fat at the same time — the recomposition approach, from your age, weight and activity.
What body recomposition actually is
Body recomposition means losing fat and building muscle at the same time, rather than bulking then cutting. It is slower than either goal alone, and it works best for beginners, people returning after a break, and anyone carrying extra fat. The two levers are eating near your maintenance calories and getting enough protein while you train.
The calculator estimates maintenance with the Mifflin-St Jeor equation and sets protein at 2 grams per kilogram of body weight — the amount research links to keeping and building muscle on a calorie-controlled diet. Protein guidance follows the Dietary Guidelines for Americans and food values come from USDA FoodData Central.
How to use the numbers
Eat around the maintenance figure on training days and, for faster fat loss, about 250 calories less on rest days. Hit the protein target every day, lift with progressive overload, and judge progress by the mirror, the tape measure and your strength — not the scale, which barely moves during recomposition.
Body recomposition, answered
Can you really lose fat and gain muscle at once?
Yes, especially if you are new to lifting, returning after a break, or carrying extra body fat. A small deficit with high protein and progressive training lets the body pull energy from fat while building muscle. Advanced lifters see it more slowly.
Why does the scale barely move?
That is the point. You are trading fat for muscle, so weight can hold steady while you get leaner. Judge progress by the mirror, photos, how clothes fit and your strength — not the scale alone.
How much protein do I need?
The target is about 2 g per kg of body weight, near the top of the evidence-based range (1.6–2.2 g/kg). Protein preserves and builds muscle while you are in a deficit, so hit it consistently.
How long does body recomposition take?
Months, not weeks. Because you are not chasing fast scale loss, changes are gradual. Recheck every 4–6 weeks and stay patient — consistency beats speed.
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