How much protein do you need per day for optimal muscle growth? This calculator is based on the meta-analysis by Morton et al. 2018: 1.6–2.2 g protein per kg body weight per day is optimal for hypertrophy.
Morton et al. (2018) analyzed 49 studies with 1,863 participants and found: 1.6 g/kg/day is the minimum threshold for maximum muscle growth. More than 2.2 g/kg provides no additional benefit.
| Body weight | Minimum (1.6g) | Optimal (2.0g) | Maximum (2.2g) |
|---|---|---|---|
| 60 kg | 96 g | 120 g | 132 g |
| 80 kg | 128 g | 160 g | 176 g |
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Try free for 14 days →Morton (2018) meta-analysis established the evidence-based range: 1.6-2.2g per kg bodyweight per day. Where in this range you should aim depends on your current goal:
| Goal | Protein (g/kg) | Example (80kg) |
|---|---|---|
| Muscle building (surplus) | 1.6-1.8 | 128-144g/day |
| Body recomposition | 2.0 | 160g/day |
| Cutting (deficit) | 2.0-2.2 | 160-176g/day |
| Maintenance | 1.6-2.0 | 128-160g/day |
Total daily intake matters far more than timing. However, distributing protein across 4-5 meals of 25-40g each optimizes muscle protein synthesis throughout the day. A meal with 30-40g within 2 hours of training is helpful but not critical: your body builds muscle over 24-48 hours, not just in a 30-minute window.
Casein before bed: 20-40g of slow-digesting protein (casein shake, Greek yogurt) before sleep maintains MPS overnight (Res 2012). Especially important during a caloric deficit.
Chicken breast (31g/100g), Greek yogurt (10g/100g), eggs (6g each), lean beef (26g/100g), fish (20-25g/100g), whey protein (25g/scoop), cottage cheese (11g/100g). Mix animal and plant sources for complete amino acid profiles. Whey protein is not superior to food. It is simply convenient for reaching your daily target.
Not enough: Most people eat 0.8-1.2g/kg, half the recommendation. This single factor limits muscle growth more than any training variable.
All in one meal: A single 120g protein meal is less effective than four 30g meals for MPS stimulation. Distribute throughout the day.
Reducing during a cut: Protein needs INCREASE in a deficit (2.0-2.2g/kg) because the body needs more amino acids to preserve muscle tissue when energy is restricted.
Chicken breast (31g/100g), whey protein (80g powder), egg whites (11g/100g), Greek yogurt 0% (10g/100g), tuna canned (26g/100g), lean beef (26g/100g), salmon (20g/100g). During a cut: prioritize highest protein-per-calorie sources. During a bulk: more flexibility. Mix animal and plant sources for complete amino acids.
Common mistakes: Not enough total protein (most eat 0.8-1.2g/kg, half the recommendation). All protein in one meal (distribute across 4 meals). Reducing protein during a cut (needs INCREASE to 2.0-2.2g/kg for muscle preservation).
Bulking: 1.6-1.8g/kg is sufficient because the caloric surplus provides a muscle-sparing effect. Focus on total calories and progressive overload.
Cutting: Increase to 2.0-2.2g/kg. The deficit creates a catabolic environment: extra protein protects existing muscle tissue from breakdown. This is the single most important nutritional adjustment during a cut.
Maintenance: 1.6-2.0g/kg depending on training volume. Higher volume phases benefit from higher protein.
Recomposition: 2.0g/kg. You are asking your body to build muscle while losing fat simultaneously: maximum protein support is essential for this to work. Combined with adequate training volume (Pelland 2024) and RIR 1-3 (Robinson 2024), high protein is the nutritional foundation for body recomposition.
Hitting 160g protein at 80kg sounds daunting, but with planning it is straightforward. A sample day: Breakfast oatmeal plus whey (35g). Lunch chicken breast plus rice (40g). Afternoon Greek yogurt plus nuts (20g). Dinner salmon plus sweet potato (30g). Evening casein shake (30g). Total: 155g across 5 meals. Each meal takes 10-15 minutes to prepare. No exotic foods, no expensive supplements: just consistent protein distribution throughout the day.
The key insight: most people do not have a protein knowledge problem. They have a protein execution problem. They know they should eat more protein but do not plan their meals accordingly. Meal prep on Sunday for the week ahead solves 80% of protein compliance issues.