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Protein Intake Calculator: How Much Protein Do I Need?
The U.S. Recommended Dietary Allowance for protein is 0.8 grams per kilogram of body weight per day, so a 70 kg (154 lb) adult needs at least 56 g. Published position stands give higher ranges: 1.0 to 1.2 g/kg for adults over 65 and 1.4 to 2.0 g/kg for people who exercise. Enter your weight and pick a range to see grams per day and per meal.
Prepared by Prospyr · Reviewed October 3, 2026 · Free, no sign-up, runs in your browser
ISSN position stand, J Int Soc Sports Nutr 2017
Protein per day: Exercising, building or keeping muscle
105–150g/day
1.4–2.0 g/kg × 74.8 kg body weight. 1.4 to 2.0 g/kg/day is sufficient for most exercising individuals.
Split over 4 meals: about 26–37 g each.
Published ranges for reference, not a personal prescription or medical advice. People with kidney disease or other conditions should follow their care team's advice.
Protein intake formula and published ranges
Daily protein (g) = body weight (kg) × grams per kg. The grams-per-kg values below are quoted from the sources listed.
| Group | Range (g/kg/day) | Source |
|---|---|---|
| Healthy adults (RDA) | 0.8 | Institute of Medicine, 2005 |
| Adults over 65 | 1.0 to 1.2 | PROT-AGE, 2013 |
| Older adults with acute or chronic disease | 1.2 to 1.5 | PROT-AGE, 2013 |
| Exercising individuals | 1.4 to 2.0 | ISSN, 2017 |
| Resistance-trained, dieting | 2.3 to 3.1 | ISSN, 2017 |
The RDA is the amount to prevent deficiency in nearly all healthy adults. Some researchers argue it is low for several groups; a 2023 review in Nutrients (Weiler and colleagues) makes that case. The calculator reports ranges as published and does not pick one for you.
Worked example: how much protein do I need
A 165 lb person is 165 ÷ 2.2046 = 74.8 kg.
- RDA: 74.8 × 0.8 = 60 g a day
- Exercising, 1.4 to 2.0 g/kg: 74.8 × 1.4 = 105 g to 74.8 × 2.0 = 150 g a day
- Split over 4 meals: 105 ÷ 4 = 26 g to 150 ÷ 4 = 37 g per meal
A 70 kg adult over 65 at 1.0 to 1.2 g/kg lands at 70 to 84 g a day, or 23 to 28 g across three meals.
Protein calculator for weight loss and per-meal protein
Dieting changes the picture only in the sources that studied it. The ISSN position stand reports that higher intakes (2.3 to 3.1 g/kg/day) may be needed to retain lean body mass in resistance-trained people during calorie-restricted periods. There is no matching published figure here for people who are not training, so the calculator does not invent one.
For meal timing, the ISSN suggests about 0.25 g/kg or 20 to 40 g per serving as a general guide and notes that evidence is mixed and depends on age and recent resistance exercise. Your total daily intake matters more than a perfect split.
Related tools
To estimate daily calories, use the TDEE calculator or the BMR calculator. To track progress, use the weight loss percentage calculator. Practices that offer weight or body composition programs can keep patient measurements together in Prospyr charting.
Frequently asked questions
How much protein do I need per day?
The RDA for healthy adults is 0.8 g per kg of body weight per day, which is 56 g for a 70 kg adult. It is a minimum that meets the needs of nearly all healthy adults. Older adults and people who exercise are covered by higher published ranges, listed in the calculator.
How much protein do I need to build or keep muscle?
The International Society of Sports Nutrition says 1.4 to 2.0 g/kg/day is sufficient for most exercising individuals. For a 75 kg person that is about 105 to 150 g a day. The position stand covers healthy, exercising people; it is not a prescription for any one person.
Protein calculator for weight loss: how much is recommended?
The RDA of 0.8 g/kg applies to adults in general and the sources used here do not set a separate figure for people dieting without training. For resistance-trained people eating fewer calories, the ISSN says 2.3 to 3.1 g/kg/day may be needed to retain lean mass. Anyone dieting should plan intake with a clinician or dietitian.
Do older adults need more protein?
Published guidance says yes. The PROT-AGE Study Group recommends an average of at least 1.0 to 1.2 g/kg/day for adults over 65, at least 1.2 g/kg for those who are exercising, and 1.2 to 1.5 g/kg for most older adults with acute or chronic disease. It treats severe kidney disease separately.
How much protein per meal?
The ISSN gives 0.25 g of high-quality protein per kg of body weight, or an absolute 20 to 40 g, as a general serving recommendation for athletes, and notes recommendations are mixed and depend on age and recent training. The calculator splits your daily total evenly across 2 to 5 meals so you can compare with that.
Should I use pounds or kilograms?
Either. Published ranges are per kilogram, so the calculator converts pounds first: divide pounds by 2.2046 to get kilograms. 165 lb is 74.8 kg.
Is a high protein intake safe for everyone?
This tool cannot say. The ranges come from position statements about healthy exercising people or older adults, and people with kidney disease or other conditions should follow their care team's advice.
Sources and scope
- Weiler M, Hertzler SR, Dvoretskiy S. Is It Time to Reconsider the U.S. Recommendations for Dietary Protein and Amino Acid Intake? Nutrients 2023 (PMC9963165)
Peer-reviewed. States the U.S. adult RDA of 0.8 g/kg/day (set by the Institute of Medicine in 2005) and its derivation.
- Jäger R, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr 2017 (PMC5477153)
1.4 to 2.0 g/kg/day for most exercising individuals; 2.3 to 3.1 g/kg/day during hypocaloric periods in resistance-trained subjects; 0.25 g/kg or 20 to 40 g per serving.
- Bauer J, 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 (PubMed 23867520)
1.0 to 1.2 g/kg/day for older adults, at least 1.2 for those exercising, 1.2 to 1.5 with acute or chronic disease.
Published ranges for reference only. Not medical or dietary advice and not a personal prescription; people with kidney disease or other conditions should follow their care team.