Protein Calculator

Find out how much protein to eat each day for your goal, from building muscle to staying healthy, and how to spread it over your meals.

Your details

kg
%
Your goal

Your results

Enter your bodyweight to see your daily protein target.

How to use it

  1. Enter your bodyweight.
  2. Pick your goal.
  3. Dieting? Add your body fat % for a more precise target, based on your lean mass.
  4. Read your daily protein target, and the amount per meal for 3 to 5 meals a day.

How it's calculated

Daily target by goal.

Goal Protein a day Source
General health 0.8 g per kg bodyweight Recommended Dietary Allowance (Institute of Medicine, 2005)
Healthy aging (65+) 1.0–1.2 g per kg PROT-AGE Study Group (Bauer et al., 2013)
Build muscle or get stronger 1.6–2.2 g per kg Morton et al. (2018); ISSN (Jäger et al., 2017) gives 1.4–2.0
Lose fat while lifting 2.3–3.1 g per kg of lean mass Helms et al. (2014); ISSN (2017)

For “Lose fat while lifting”, lean mass = bodyweight × (1 − body fat % ÷ 100). Without a body fat %, the calculator uses the muscle-building range (1.6–2.2 g per kg of bodyweight) instead.

Example: 80 kg at 20% body fat has 64 kg of lean mass, so 2.3–3.1 g/kg gives 147 to 198 g a day.

Per meal. The table splits the middle of your range over 3, 4 or 5 meals. Schoenfeld and Aragon (2018) suggest about 0.4 g per kg per meal over at least four meals for building muscle. Results are rounded to 5 g.

Limits. These are ranges from studies on groups of people. Your needs depend on your training, total calories and health. People with kidney disease should follow their doctor’s advice.

Sources

  1. Morton, R. W., Murphy, K. T., McKellar, S. R., Schoenfeld, B. J., Henselmans, M., Helms, E., Aragon, A. A., Devries, M. C., Banfield, L., Krieger, J. W., & Phillips, S. M. (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), 376–384.
  2. Jäger, R., Kerksick, C. M., Campbell, B. I., et al. (2017). International Society of Sports Nutrition position stand: protein and exercise. Journal of the International Society of Sports Nutrition, 14, 20.
  3. Helms, E. R., Aragon, A. A., & Fitschen, P. J. (2014). Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. Journal of the International Society of Sports Nutrition, 11, 20.
  4. Bauer, J., Biolo, G., Cederholm, T., et al. (2013). Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. Journal of the American Medical Directors Association, 14(8), 542–559.
  5. Institute of Medicine (2005). Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: National Academies Press.
  6. Schoenfeld, B. J., & Aragon, A. A. (2018). How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution. Journal of the International Society of Sports Nutrition, 15, 10.

Questions

How much protein do I need to build muscle?

About 1.6 g per kg of bodyweight a day (0.7 g per lb) covers most people. A large meta-analysis found gains level off around there, with up to 2.2 g/kg possibly helping a little more.

Do I need more protein when dieting?

Yes. Eating in a deficit makes it harder to keep muscle. Research on lean lifters suggests 2.3 to 3.1 g per kg of lean mass while dieting, which is why the calculator asks for your body fat % for that goal.

How much protein can I eat in one meal?

There's no hard limit; your body uses it all. For building muscle, spreading protein over 3 to 5 meals of about 0.4 g per kg each works well.

Is a high protein diet safe?

For healthy adults, the intakes in this calculator are within ranges studied as safe. If you have kidney disease or another medical condition, ask your doctor what's right for you.

Updated November 9, 2026.