Recommended grams of protein per day by goal, body weight, and age.
Protein is the structural macronutrient: it builds muscle, immune cells, hair, nails, neurotransmitters, and every enzyme in your body. Unlike carbs and fats, your body has no real protein storage — uneaten protein is either burned for energy or excreted as urea. That makes the daily intake question pivotal: too little and you lose lean mass (especially during a fat-loss diet), too much wastes money and stresses kidneys (in healthy people, the latter is overstated; in CKD patients it is real). The right number depends sharply on your activity and body composition goal. The Recommended Daily Allowance of 0.8 g/kg was set in 1968 to prevent deficiency in mostly sedentary adults, and it remains the floor on most national nutrition labels. Modern sport-nutrition science has shown that adults pursuing fat loss, hypertrophy, or athletic performance need 1.4–2.2 g/kg, often double the RDA. This calculator picks the right factor for your goal and converts it to grams of protein per day, with a per-meal breakdown to maximize muscle protein synthesis.
Daily protein (g) = body mass (kg) × factor (g/kg)
The factor is keyed to goal: - Sedentary: 0.8 g/kg (RDA — bare deficiency floor) - Active adult: 1.2 g/kg (general fitness, recreational sport) - Endurance athlete: 1.4 g/kg (long-distance runners, cyclists) - Strength training: 1.7 g/kg (resistance training 3+ sessions/week) - Bulk / hypertrophy: 1.8 g/kg (active mass gain) - Cut / fat loss: 2.2 g/kg (preserves lean mass during caloric deficit)
Older adults (≥65) get a 10% bump because of anabolic resistance — they need more protein to trigger the same muscle protein synthesis response. Per-meal breakdown spreads the daily target across your meals (typically 4) for a roughly even amino-acid pulse.
Pick your unit (kg or lb), enter body weight, choose your goal from the six presets, set your age, and choose how many meals per day you typically eat. The calculator returns: - Daily protein in grams (the headline) - Effective factor — the g/kg multiplier used (with senior bonus if applicable) - Per-meal target — split equally across meals - kcal from protein — at 4 kcal/g, this is what protein contributes to your TDEE
The gauge graphic shows where your factor sits on the spectrum from RDA (gray) to contest-prep (red).
A 70 kg active office worker chooses active goal: 70 × 1.2 = 84 g/day, split across 4 meals at 21 g each — easily covered by 100 g of chicken breast at lunch (31 g) and dinner (31 g), 30 g of whey at breakfast (24 g), and a yogurt in the afternoon. An 80 kg powerlifter cutting weight before a meet: 80 × 2.2 = 176 g/day — a more challenging target, often requiring 250 g of meat or fish daily. A 70-year-old woman maintaining muscle mass at 60 kg active: 60 × 1.2 × 1.10 (senior bonus) = 79 g/day — close to the active-adult target, but the senior bump matters for sarcopenia prevention.
For elite athletes or contest-prep bodybuilders, factors of 2.5–3.0 g/kg are sometimes used, though evidence above 2.2 is thin. For surgical recovery and burn patients, 1.5–2.0 g/kg helps tissue repair. For weight-loss patients on very-low-calorie diets (VLCD), protein climbs to 30–40% of total calories to preserve lean mass. Pre-sleep casein (30 g slow-digesting) sustains amino-acid availability overnight and modestly improves morning recovery. EAA (essential amino acid) supplementation can be useful for older adults with low appetite — 6–10 g of EAAs delivers the leucine pulse without the calories of full meals. Plant-based athletes should pair complementary sources (rice + beans, hummus + bread) per meal to get a complete amino-acid profile, or rely on soy/pea isolate supplements that already score near 1.0 on DIAAS.