Protein Calculator
Press Calculate to see the results.
This protein calculator estimates how many grams of protein you need each day, based on your body size, sex, age and activity level, and compares several official and sports nutrition guidelines.
Protein needs are usually expressed in grams per kilogram of body weight. The calculator applies the main reference values: the US Recommended Dietary Allowance, the range of calories from protein considered healthy, the World Health Organization's safe intake, and the higher targets used in sports nutrition for people who train regularly. It also estimates your daily calories from your body measurements and activity so the percentage-based range can be expressed in grams.
These are values for healthy people. Needs can be different during pregnancy and breastfeeding, recovery from surgery or serious illness, and for people with kidney or liver disease, who should follow their health care team's advice.
What are proteins?
Proteins are large molecules built from chains of amino acids. The body uses them for almost everything: structural tissue such as muscle, skin, hair and bone matrix; enzymes that drive chemical reactions; hormones such as insulin; antibodies; and transport molecules such as hemoglobin. Proteins are constantly broken down and rebuilt, so a regular supply from food is needed.
Twenty amino acids make up human proteins. Nine are essential, meaning the body cannot make them in sufficient amounts and they must come from the diet: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Foods that provide all nine in good proportions are called complete proteins. Meat, poultry, fish, eggs and dairy are complete, as are soy foods and quinoa. Most other plant foods are low in one or more essential amino acids, but eating a variety of them over the day, such as grains with beans, provides a complete mix.
Protein supplies 4 Calories per gram. Unlike fat and carbohydrate, the body has no dedicated store of it, so excess is used for energy or converted and stored as fat, while too little over time leads to loss of muscle and weakened immunity.
How much protein do I need?
The National Academies set the adult Recommended Dietary Allowance at 0.8 grams of protein per kilogram of body weight per day, enough to meet the needs of nearly all healthy adults who are not very active. For someone weighing 160 pounds (72.6 kg), that is about 58 grams. The same body sets an Acceptable Macronutrient Distribution Range of 10% to 35% of calories from protein for adults, which allows a broad range of healthy diets. The RDA is a minimum to prevent deficiency rather than an optimal intake, and most Americans already eat more than it.
Higher intakes are useful in some situations. A joint position statement from the American College of Sports Medicine, the Academy of Nutrition and Dietetics and Dietitians of Canada recommends 1.2 to 2.0 g/kg a day for athletes, and many researchers suggest 1.0 to 1.2 g/kg for adults over 65 to slow age-related muscle loss. Eating more protein during weight loss also helps preserve muscle.
| Group | RDA (grams per day) |
|---|---|
| Children 1–3 years | 13 |
| Children 4–8 years | 19 |
| Children 9–13 years | 34 |
| Girls 14–18 years | 46 |
| Boys 14–18 years | 52 |
| Women 19+ years | 46 |
| Men 19+ years | 56 |
| Pregnancy or breastfeeding | 71 |
Protein (g/day) = body weight (kg) × g/kg target · AMDR grams = daily calories × (0.10 to 0.35) ÷ 4
Daily calories are estimated as BMR (Mifflin-St Jeor or Katch-McArdle) × activity factor. Protein provides 4 Calories per gram.
Common targets expressed per kilogram of body weight:
| Situation | Protein (g per kg per day) | Source |
|---|---|---|
| Healthy adults (RDA) | 0.8 | National Academies |
| Safe intake for adults | 0.83 | WHO/FAO/UNU |
| Adults over 65 | 1.0–1.2 | PROT-AGE study group |
| Athletes and regular exercisers | 1.2–2.0 | ACSM, AND and Dietitians of Canada |
| Maximizing muscle gain from resistance training | About 1.6 | Meta-analysis, Morton et al., 2018 |
Foods high in protein
Both animal and plant foods can supply plenty of protein. Animal sources such as poultry, fish, eggs and dairy provide complete protein along with nutrients such as vitamin B12, iron and zinc. Choosing lean cuts and limiting processed meats such as bacon, sausage and deli meats is advised, because processed meat is linked to a higher risk of colorectal cancer and heart disease.
Plant sources, including beans, lentils, peas, soy foods, nuts, seeds and whole grains, bring fiber and healthy fats with their protein and are linked to lower risks of heart disease. The Dietary Guidelines for Americans encourage a variety of protein foods, including seafood at least twice a week and more beans, peas and lentils. Plant proteins are slightly less digestible and some are low in particular amino acids, so people on vegan diets do well to eat a range of sources and may aim slightly above the RDA.
Spreading protein across meals, roughly 20 to 40 grams each for most adults, supports muscle maintenance better than eating most of it at dinner. Protein powders are convenient but not necessary for most people, who can meet their needs from food. The values below are approximate, from USDA FoodData Central.
| Food | Serving | Protein (g) |
|---|---|---|
| Chicken breast, roasted | 3 oz (85 g) | 26 |
| Lean beef, cooked | 3 oz (85 g) | 22 |
| Salmon, cooked | 3 oz (85 g) | 22 |
| Tuna, canned in water | 3 oz (85 g) | 20 |
| Shrimp, cooked | 3 oz (85 g) | 20 |
| Cottage cheese, low fat | 1 cup | 28 |
| Greek yogurt, plain nonfat | 6 oz (170 g) | 17 |
| Milk | 1 cup | 8 |
| Egg | 1 large | 6 |
| Tofu, firm | ½ cup (126 g) | 20 |
| Tempeh | 3 oz (85 g) | 16 |
| Edamame, cooked | 1 cup | 18 |
| Lentils, cooked | 1 cup | 18 |
| Black beans, cooked | 1 cup | 15 |
| Chickpeas, cooked | 1 cup | 15 |
| Quinoa, cooked | 1 cup | 8 |
| Pumpkin seeds | 1 oz (28 g) | 9 |
| Peanut butter | 2 tbsp | 7 |
| Almonds | 1 oz (28 g) | 6 |
Frequently asked questions
How much protein do I need a day?
The RDA for healthy adults is 0.8 g per kg of body weight, about 58 grams for a 160-pound person. Active people often benefit from 1.2 to 2.0 g/kg.
Can I eat too much protein?
Intakes up to about 2 g/kg appear safe for healthy adults. People with kidney disease should follow their doctor's advice, as high intakes can strain damaged kidneys.
Do I need protein supplements?
Most people can meet their needs from food. Supplements can be convenient for athletes or people with high needs or small appetites.
Can vegetarians and vegans get enough protein?
Yes. Eating a variety of beans, lentils, soy foods, nuts, seeds and whole grains provides all the essential amino acids.
When should I eat protein?
Spread it across your meals, around 20 to 40 grams each for most adults, and include some after resistance training.
How do I calculate my protein needs?
Convert your weight to kilograms (pounds ÷ 2.2046) and multiply by a grams-per-kilogram target: 0.8 for the RDA, or 1.2 to 2.0 if you train regularly. A 160-pound (72.6 kg) person needs about 58 grams at 0.8 g/kg and about 116 grams at 1.6 g/kg. Another check is the AMDR: 10% to 35% of daily calories, divided by 4 Calories per gram.
How do I count how much protein I eat?
Read the grams of protein on Nutrition Facts labels and log what you eat for a few typical days, weighing or measuring portions at first. For foods without labels, use a reference such as USDA FoodData Central or the table above: 3 ounces of roasted chicken breast has about 26 grams and a large egg about 6. Add up the day's total and compare it with your target from the calculator.
Results are estimates for educational purposes and are not medical advice. Talk to a doctor or other qualified health professional about your situation.
Updated by Calculator.hair. How we build and check our calculators