Protein Need by Lean Mass Calculator

First, the tool selects a “calculation mass”: lean body mass if you choose that basis, otherwise total body weight. It then calculates protein as: protein target (g/day) = calculation mass (kg) × protein factor (g/kg/day). A modest display range is also shown by applying a small band around your chosen factor.

Lean mass is often more relevant when body fat is higher, because it avoids “overcounting” protein needs based on extra fat mass. If your lean body mass is much lower than your total weight, the lean-mass option may better match the intent of protein goals for training or dieting. If your lean mass closely tracks your total weight, either basis will usually produce similar results.

If you turn on the kidney safety flag and select a higher protein factor, the calculator will display a caution that you may need clinician guidance. This tool uses a simplified rule and cannot account for kidney disease stage, dialysis status, medications, pregnancy, or other medical factors. If you have known kidney issues or were advised to limit protein, confirm your target with a healthcare professional.