Protein Intake Calculator
Work out the adult protein RDA for your body weight, and cross-check it against the published AMDR range.
Result
Enter weight to see the result.
https://calcgallery.com/nutrition-energy/protein-intake-calculator/
How to use the Protein Intake Calculator
- Enter your body weight in pounds or kilograms.
- Read the RDA figure, which is 0.8 grams per kilogram of body weight.
- Optionally add your daily calories for the AMDR cross-check, which works from energy instead.
- Treat the RDA as a floor for adequacy rather than a target to aim at.
How it is calculated
Two published figures, doing two different jobs.
The RDA scales with body weight:
protein g/day = 0.8 × body weight in kgThe Institute of Medicine set this as the intake that meets the requirements of 97 to 98 percent of healthy adults. That definition matters: it is a threshold designed so that almost nobody falls short, which makes it a floor for adequacy rather than a recommendation about what is best.
The AMDR scales with energy instead. The acceptable macronutrient distribution range for protein is 10 to 35 percent of daily calories, converted to grams at 4 kilocalories per gram. Entering a calorie figure shows that band alongside the RDA.
For a 70 kilogram adult eating 2,200 calories, the RDA is 56 grams and the AMDR spans 55 to 192 grams. The RDA sits almost exactly at the bottom of the acceptable range, which is a fair summary of what these two documents are each saying.
Why no athletic range is shown
Nearly every competing calculator offers bands of 1.2, 1.6 or 2.2 grams per kilogram for various levels of training. Those numbers may well be right. They are not shown here because they could not be traced to a source precise enough to cite — following them back leads to other calculators, not to a position stand with a page number.
This site does not ship a constant it cannot attribute, so the page shows the figures it can and names the documents worth reading for the rest: the joint position stand from the American College of Sports Medicine and the Academy of Nutrition and Dietetics, and the International Society of Sports Nutrition position stand on protein and exercise.
That is a deliberate gap, not an oversight.
What is out of scope
Kidney disease changes protein requirements substantially and in a direction that depends on the condition and its stage. Pregnancy and lactation have their own separate DRI values. Older adults are the subject of an active research literature suggesting the adult RDA may be low for preserving muscle mass with age. None of those is modelled here, and all of them are clinical questions rather than arithmetic ones.
Practical tips
Read the RDA as a minimum. It is the number below which a healthy adult is likely to be short, not the number at which anything is optimised.
The AMDR band is very wide. A hundred and forty grams separates its ends for a typical intake. That width reflects genuine uncertainty about what is best rather than precision about what is adequate.
Spread it across the day if it matters to you. Total daily intake is what these figures describe. Distribution across meals is a separate question that the RDA and the AMDR say nothing about.
Scale to lean mass if your body fat is high. The RDA is per kilogram of total weight, which for someone carrying substantial fat produces a figure driven partly by tissue with little protein requirement.
Whole foods make the arithmetic easier than it looks. A hundred grams of chicken breast is roughly thirty grams of protein, and most people reach the RDA without deliberate effort.
With your numbers
- 0.8 g per kg × 165 lb (74.8 kg) = 60 g a day
Quick reference
The RDA is the intake that meets the needs of almost all healthy adults. It is a floor for adequacy, not a performance target.
| Example | Protein per day, RDA |
|---|---|
| 120 lb | 44 g |
| 150 lb | 54 g |
| 165 lb | 60 g |
| 200 lb | 73 g |
| 60 kg | 48 g |
| 70 kg | 56 g |
| 70 kg at 2,200 kcal | 56 g |
| 90 kg | 72 g |
Where the numbers come from
The fixed figures this calculator relies on, and the published source each one was checked against. How the calculators are built and checked
3 sources
Institute of Medicine, Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2002/2005), chapter 10; Summary Tables p. 1324, footnote b: "0.8 g/kg body weight for the reference body weight" for adults.
Used for
- Adult protein recommended dietary allowance per kilogram.
Institute of Medicine, Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2002/2005), Summary Tables, p. 1325, Acceptable Macronutrient Distribution Ranges, adults: protein 10-35, carbohydrate 45-65, fat 20-35 percent of energy. https://nap.nationalacademies.org/read/10490/chapter/32
Used for
- Lower protein AMDR for adults.
- Upper protein AMDR for adults.
Merrill AL, Watt BK, Energy Value of Foods: Basis and Derivation, USDA Agriculture Handbook No. 74 (slightly revised February 1973), p. 48, the "general factors 4, 9, 4", https://www.ars.usda.gov/ARSUserFiles/80400525/Data/Classics/ah74.pdf
Used for
- General Atwater energy factor for protein.
Common questions about the Protein Intake Calculator
- Is the RDA enough if I lift weights?
- The RDA was not set to answer that. It is defined as the intake meeting the needs of 97 to 98 percent of healthy adults, which is a threshold for avoiding deficiency, not a figure optimised for training adaptation. Sports nutrition bodies publish higher ranges for athletes. This page does not show one, for the reason given below.
- Why is there no athletic range on this page?
- Because no figure could be traced to a source this site is able to cite precisely. The 1.6 to 2.2 grams per kilogram range that appears on nearly every competing calculator is presented without a page reference, and following it back leads to other calculators rather than to a position stand. Rather than repeat a number of unknown provenance, this page ships the figures it can attribute and says so. If you want the athletic ranges, the ACSM, Academy of Nutrition and Dietetics and ISSN position stands are the documents to read.
- Can you eat too much protein?
- The IOM set the acceptable range at 10 to 35 percent of energy and did not establish an upper tolerable intake level for protein, noting a lack of evidence on which to base one. That is not the same as saying any amount is fine. Existing kidney disease changes the picture entirely and is a clinical question.
- Per kilogram of body weight or of lean mass?
- The RDA is stated per kilogram of total body weight, which is how it is applied here. Some practitioners prefer to scale protein to lean mass instead, on the reasoning that fat tissue has little protein requirement, and that produces a lower figure for someone carrying more fat. That is a defensible adjustment and it is not what the RDA says.
- Why do the two figures on this page disagree so much?
- They answer different questions. The RDA scales with your body: 0.8 grams for every kilogram you weigh. The AMDR scales with what you eat: 10 to 35 percent of your energy. For a 70 kilogram adult eating 2,200 calories the RDA is 56 grams while the AMDR spans 55 to 192 grams, so the RDA sits right at the bottom of a very wide acceptable range.