Nutrition
Protein calculator: how much protein do you need a day?
Enter your weight, age and how active you are to see how many grams of protein a day the published recommendations point to for you. The figures come from the US Recommended Dietary Allowance, the sports nutrition position statements and the PROT-AGE recommendations for people over 65, all set in grams per kilogram of body weight.
Enter your values above to see your result and what it means.
How much protein do I need a day?
For a healthy adult who does little exercise, the US Recommended Dietary Allowance is 0.8 g of protein per kilogram of body weight per day, about 58 g for someone weighing 160 lb (72.6 kg). Regular training raises the published figure to 1.2-2.0 g/kg, training to build or keep muscle to 1.4-2.0 g/kg, and the PROT-AGE group recommends at least 1.0-1.2 g/kg for people over 65. To use a figure, convert your weight to kilograms (pounds divided by 2.2) and multiply.
| Body weight | RDA (0.8 g/kg) | Over 65 (1.0-1.2 g/kg) | Regular training (1.2-2.0 g/kg) | Building muscle (1.4-2.0 g/kg) |
|---|---|---|---|---|
| 120 lb (54.4 kg) | 44 g | 54-65 g | 65-109 g | 76-109 g |
| 140 lb (63.5 kg) | 51 g | 64-76 g | 76-127 g | 89-127 g |
| 160 lb (72.6 kg) | 58 g | 73-87 g | 87-145 g | 102-145 g |
| 180 lb (81.6 kg) | 65 g | 82-98 g | 98-163 g | 114-163 g |
| 200 lb (90.7 kg) | 73 g | 91-109 g | 109-181 g | 127-181 g |
| 220 lb (99.8 kg) | 80 g | 100-120 g | 120-200 g | 140-200 g |
| 250 lb (113.4 kg) | 91 g | 113-136 g | 136-227 g | 159-227 g |
Where each number comes from
The 0.8 g/kg RDA is from the Institute of Medicine Dietary Reference Intakes (2005), chapter 10 on protein and amino acids. The 1.2-2.0 g/kg range is from the 2016 joint position statement on nutrition and athletic performance by the Academy of Nutrition and Dietetics, Dietitians of Canada and the American College of Sports Medicine. The 1.4-2.0 g/kg range is from the International Society of Sports Nutrition position stand on protein and exercise (Jäger et al., 2017). The 1.0-1.2 g/kg figure for people over 65 is from the PROT-AGE Study Group (Bauer et al., 2013). The calculator applies one figure per option and shows which one it used.
| Group | Grams per kg per day | Source |
|---|---|---|
| Healthy adult, little exercise | 0.8 (RDA) | Institute of Medicine, 2005 |
| Regular training or sport | 1.2-2.0 | AND, Dietitians of Canada, ACSM, 2016 |
| Building or keeping muscle with exercise | 1.4-2.0 | ISSN position stand, 2017 |
| Over 65 | 1.0-1.2 (1.2 or more if active) | PROT-AGE, 2013 |
| Over 65 with acute or chronic illness | 1.2-1.5 | PROT-AGE, 2013 |
Kidney disease and other reasons to ask first
The ranges on this page describe healthy adults. People with chronic kidney disease have separate, usually lower, targets in the KDOQI nutrition guideline, and PROT-AGE excludes older people with severe kidney disease who are not on dialysis from its higher recommendation. If you have kidney disease, are pregnant or breastfeeding, or are being treated for any condition that affects how you eat, your doctor or a registered dietitian should set your protein target.
What this calculator does not do
It gives a reference range for total daily protein. It does not plan meals, count the protein in foods, or assess what you eat now. It uses your actual body weight, as the RDA and the position statements do. For weight loss, muscle gain or a medical condition, the right amount is a decision to make with a dietitian who knows your health and goals.
Frequently asked questions
How much protein do I need a day?
For a healthy adult with little exercise, the RDA is 0.8 g per kilogram of body weight, which is 58 g a day at 160 lb (72.6 kg) and 73 g at 200 lb. People who train regularly, people building muscle and adults over 65 have higher published ranges; the calculator above applies the one that fits you.
How much protein do I need to build muscle?
The International Society of Sports Nutrition concludes that 1.4 to 2.0 g per kilogram of body weight a day is sufficient for most exercising people to build and keep muscle. At 180 lb (81.6 kg), that is about 114 to 163 g a day, ideally spread across meals every 3 to 4 hours.
How much protein should a 70-year-old eat?
The PROT-AGE Study Group recommends that people over 65 average at least 1.0 to 1.2 g per kilogram a day, 1.2 g/kg or more if they exercise, and 1.2 to 1.5 g/kg for most people with an acute or chronic illness. People with severe kidney disease who are not on dialysis are the exception and may need less, so they should ask their doctor.
Is a high-protein diet bad for your kidneys?
In healthy, trained adults, the studies reviewed by the ISSN found no harm to kidney or liver function at intakes up to about 2.5 to 3.3 g/kg a day over periods of up to a year. People who already have kidney disease are a different case: their protein target comes from their doctor or dietitian, following guidelines such as KDOQI.
Should I use my current weight or my ideal weight?
The RDA, the sports nutrition statements and PROT-AGE are all expressed per kilogram of body weight, and the calculator uses the weight you enter. If your weight is far from what is typical for your height, ask a dietitian which reference weight suits you.
Sources
- Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: National Academies Press; 2005 (chapter 10, Protein and Amino Acids).
- Thomas DT, Erdman KA, Burke LM. American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance. Med Sci Sports Exerc. 2016;48(3):543-568.
- Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20.
- Bauer J, Biolo G, Cederholm T, et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. J Am Med Dir Assoc. 2013;14(8):542-559.
- Ikizler TA, Burrowes JD, Byham-Gray LD, et al. KDOQI Clinical Practice Guideline for Nutrition in CKD: 2020 Update. Am J Kidney Dis. 2020;76(3 Suppl 1):S1-S107.