Energy and macros

Calculate Protein Needs

How much protein you need per day depends on body weight and phase. The calculator shows the range from the research instead of false precision.

Phase

Needed in a Cut because the range is based on lean mass. Estimate body fat

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How it works

For building and maintaining, the calculator uses 1.6 to 2.2 g of protein per kg of body weight. The range comes from the meta-analysis by Morton et al. (2018): above roughly 1.6 g per kg, more protein brought no further measurable benefit for lean mass on average, and the upper limit of the confidence interval was about 2.2 g.

In a Cut, your needs go up because the body breaks down muscle more easily in a deficit. Helms et al. (2014) recommend 2.3 to 3.1 g per kg of lean mass for lean strength athletes in a deficit. That is why the calculator needs your body fat percentage here.

The amount per meal is the daily amount divided by your number of meals.

How to use your result

In a Lean Bulk, aim for the middle of the range, in a Cut rather toward the top. According to the evidence, going above the upper limit brings no additional muscle growth and costs calories you are missing for carbs and fat.

Spread your protein across several meals. Schoenfeld and Aragon (2018) suggest about 0.4 g per kg of body weight per meal across at least four meals. Then enter the daily amount into the macro calculator.

If you have a kidney condition, talk to your doctor about your protein intake first.

Formula and source

Build and maintain: protein (g/day) = body weight (kg) × 1.6 to 2.2
Cut: lean mass (kg) = body weight (kg) × (1 - body fat (%) ÷ 100)
Cut: protein (g/day) = lean mass (kg) × 2.3 to 3.1
Per meal = protein per day ÷ meals

Morton RW et al. (2018): A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine 52(6). Helms ER et al. (2014): A systematic review of dietary protein during caloric restriction in resistance trained lean athletes. International Journal of Sport Nutrition and Exercise Metabolism 24(2). Schoenfeld BJ, Aragon AA (2018): How much protein can the body use in a single meal for muscle-building? Journal of the International Society of Sports Nutrition 15.

Frequently asked questions

No, that is too simple. Larger portions are also absorbed and used. Several protein-rich meals across the day are still a practical strategy (Schoenfeld and Aragon 2018).

In a calorie deficit, the risk of losing muscle along with fat goes up, especially for lean people. More protein together with strength training helps keep lean mass. Protein-rich meals also keep you full.

For healthy people, there is no reliable evidence of harm within the range of this calculator. If you have a kidney condition or are unsure, you should talk to your doctor about your protein intake.

Yes, it counts toward your daily amount. Some individual plant sources contain less of certain essential amino acids. With varied sources or a bit more total protein, you make up for that.

All results are estimates and do not replace advice from a doctor or dietitian.

Related calculators

Macro calculator Protein, fat and carbs from your calorie target. TDEE calculator Basal metabolic rate and total daily energy expenditure using Mifflin-St Jeor. FFMI calculator Fat-free mass relative to height, after Kouri 1995.