How Much Protein Do You Need?
The recommended dietary allowance (RDA) for protein is 0.8 g/kg — the minimum to prevent deficiency, not the optimum for performance. For muscle building, research consistently supports 1.6–2.2 g/kg of bodyweight per day. At this range, muscle protein synthesis is maximized regardless of training status. Beyond 2.2 g/kg, additional protein adds calories without adding muscle.
Formula & Background
This calculator applies research-backed multipliers: sedentary maintenance uses the 0.8 g/kg RDA; moderate activity adds 10–20%; muscle-building targets 1.8 g/kg (or 2.2 g/kg for very active trainees); endurance athletes need 1.4 g/kg to repair muscle fiber micro-tears from sustained cardio. Conversion from lbs: 1 lb = 0.4536 kg.
Calculation Example
170 lb (77 kg) male, muscle-building goal, moderate activity: 77 × 1.8 = 139 g/day. Split across 4 meals: ~35 g per meal — roughly 5 oz chicken breast + 2 eggs per meal.
Expert Tips
- Spread protein across 4+ meals at 20–40 g each — your body can’t use 100 g in one sitting for muscle repair.
- Leucine content matters most: aim for at least 2–3 g leucine per meal (found in ~30 g whey, or ~4 oz chicken).
- Plant-protein users: pair legumes + grains (e.g., lentils + rice) in the same meal to cover all essential amino acids.
- When cutting calories, go to the high end (2.0–2.2 g/kg) to preserve muscle mass during a caloric deficit.