Protein Intake Calculator
How much protein should you eat per day? This free protein intake calculator gives you a daily gram range, a single recommended target, and a per-meal split — based on your body weight (or lean body mass, if you know your body fat percentage), your activity level, and whether you are cutting, maintaining, or building muscle. Everything runs in your browser.
Why the RDA Is Not Your Target
The RDA of 0.8 g per kg of body weight is the minimum that prevents deficiency in sedentary adults — it was never designed as an optimum for people who train or diet. Research on resistance training supports 1.6–2.2 g/kg for building muscle, and cutting diets do better with 1.6–2.4 g/kg because protein protects lean mass and keeps you full in a calorie deficit. The calculator shows the RDA alongside your personalized range so you can see the difference.
Body Weight vs Lean Body Mass
Setting protein per kilogram of total weight overshoots at higher body-fat levels, because fat tissue needs little protein. Provide a body fat percentage and the calculator switches to lean-mass targets (for example 2.0–2.6 g per kg of lean mass on a cut) — a more precise prescription for the tissue that actually uses it. A two-minute tape measurement with the Navy method is enough for a workable estimate.
Spreading Protein Across Meals
Muscle protein synthesis responds best to repeated doses of roughly 25–40 g. The calculator divides your daily target across 3, 4, or 5 meals so each one lands in that effective range — usually easier to eat, too.