Protein Intake Calculator
Work out how much protein to eat per day from your body weight, training goal and optional body fat percentage.
Enter your body weight — your protein target updates as you type.
- Daily protein target
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- Recommended range
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- Per kilogram
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- Calories from protein
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- Per meal
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- Lean body mass
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- Lean-mass basis (2.3–3.1 g/kg LBM)
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These numbers are estimates from published population guidelines, not medical advice. Protein needs vary with training, health and diet, and people with kidney or liver conditions, pregnancy or an eating disorder should not follow generic targets. Ask a doctor or a registered dietitian before making big changes.
How it works
The calculator uses the standard body-weight method: daily protein (g) = body weight
(kg) × g/kg factor. The factors come from the ISSN position stand on protein and
exercise (Jäger et al., 2017) and the ACSM / Academy of Nutrition and Dietetics joint
position on nutrition and athletic performance — 0.8–1.0 g/kg as the sedentary RDA baseline,
1.2–1.6 g/kg for recreational or endurance training, 1.6–2.2 g/kg for strength training and
muscle gain, 1.8–2.4 g/kg while dieting to keep muscle, and 1.0–1.2 g/kg for maintenance
after 65 (PROT-AGE). The headline target is the midpoint of the range for your goal. Pounds
are converted with 1 lb = 0.45359237 kg.
Protein supplies 4 kcal per gram, so the calorie line is simply your target × 4. The per-meal figure divides the target by the number of meals you eat, which is a practical way to hit the roughly 0.4 g/kg per sitting that stimulates muscle protein synthesis. If you enter a body fat percentage the tool also shows your lean body mass (weight × (1 − body fat %)) and the lean-mass-based range of 2.3–3.1 g/kg LBM that Helms et al. (2014) recommend for lean athletes in a calorie deficit — useful if you carry a lot of fat mass, where body-weight formulas overshoot. Everything is computed in your browser: your weight is never uploaded, and there are no ads or sign-ups.
Frequently asked questions
How much protein do I need per day?
The usual method is grams of protein per kilogram of body weight. The RDA baseline for sedentary adults is 0.8–1.0 g/kg; recreational exercisers and endurance athletes are generally advised 1.2–1.6 g/kg; the ISSN position stand on protein and exercise puts strength trainees building muscle at 1.6–2.2 g/kg; dieting while keeping muscle sits around 1.8–2.4 g/kg; and PROT-AGE suggests 1.0–1.2 g/kg for maintenance after 65. An 80 kg lifter therefore lands at roughly 128–176 g per day, with 152 g as the midpoint target.
Should I base protein on total body weight or lean body mass?
For most people total body weight is fine and simpler. If you carry a lot of fat mass, body-weight formulas overshoot, because fat tissue does not drive protein needs — so the calculator also shows a lean-body-mass figure when you enter a body fat percentage. Lean mass is weight × (1 − body fat %), and Helms et al. (2014) recommend 2.3–3.1 g per kg of lean mass for lean athletes in a calorie deficit. At 80 kg and 20% body fat that is 64 kg of lean mass, or about 147–198 g of protein.
Does it matter how I spread protein across the day?
Somewhat. Muscle protein synthesis responds to a per-meal dose of roughly 0.4 g per kg of body weight, so splitting your daily total over three to five meals is a practical way to hit that repeatedly rather than eating most of your protein at dinner. The calculator divides your target by the number of meals you enter. Total daily intake still matters most — the per-meal split is a refinement, and these figures are population estimates, not medical advice.