The protein calculator determines your optimal daily protein intake based on your body weight, activity level, and fitness goal. Protein needs vary dramatically — from 0.8g/kg for sedentary adults to 2.5g/kg for strength athletes in hard training.
Protein is the most important macronutrient for body composition. It builds and repairs muscle tissue, supports immune function, and increases satiety. Research consistently shows benefits up to 2.2g per kg of body weight for muscle building.
Protein quality matters — animal proteins (meat, eggs, dairy) provide all essential amino acids. Plant proteins require combining sources (e.g., rice + beans) to achieve complete amino acid profiles.
Reach for this calculator when you need a standardised health metric to discuss with a healthcare provider or to use as a baseline for a fitness programme. The result gives you a number that carries more meaning than subjective assessments.
The most common mistake is treating the result as a precise measurement rather than an evidence-based estimate. All body metric calculators have margins of error — use the result as a tracking baseline, not a clinical diagnosis.
A personal trainer uses the calculator with a new client to set a measurable starting point. Re-running the calculation at 4-week intervals provides an objective progress metric that supports motivation and programme adjustments.
Daily Protein Target Formula
Protein (g) = Body Weight (kg) × Protein Factor
Protein Factor: 0.8 (sedentary) to 2.5 (strength athlete)
Protein provides 4 kcal per gram. Convert weight in lbs to kg by dividing by 2.205.
An 80kg person training 4× per week for muscle building.
Result: Daily protein target: 160g (640 kcal) — spread over 4 meals of ~40g each
Sedentary adults: 0.8g/kg. Regular exercisers: 1.2–1.6g/kg. Muscle building: 1.6–2.2g/kg. The upper range shows diminishing returns but no harm.
Chicken breast (100g) = 31g protein. Eggs (2) = 12g. Greek yogurt (200g) = 18g. Canned tuna (100g) = 25g. Lentils (100g cooked) = 9g.
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