Protein Calculator

What 1 gram per pound actually means

It is the most repeated number in fitness, and it is a rule of thumb rather than a published recommendation. One gram per pound is about 2.2 grams per kilogram — roughly 38% above the top of the federal serving goal, and at or just past the upper edge of what the muscle-gain evidence supports.

It is easy arithmetic, which is most of why it spread. For someone training hard it lands in a defensible place. For most other adults it is more protein than the evidence asks for. The calculator shows it every time so you can see where it sits against your own goal rather than guessing.

Protein and weight loss

Protein does not cause weight loss. Energy balance determines whether body weight goes up or down. What higher protein intake is associated with, while eating in a deficit, is holding on to more lean mass and feeling fuller — both of which can make a deficit more sustainable. That is worth having, and it is a different claim from "protein burns fat".

One limitation worth naming: applying grams per kilogram to total body weight can overstate needs at higher body-fat levels, because protein requirements track lean mass more closely than total mass. The calculator flags weights outside its typical band rather than quietly substituting a different figure.

Protein and muscle gain

Protein supports the adaptation that training drives. It does not build muscle on its own, and eating more of it past a point does not produce more. The pooled evidence puts that point at roughly 1.62 g/kg per day, with the confidence interval reaching about 2.2. Training stimulus and adequate total energy matter more than the last 20 grams.

Splitting protein across the day

Spreading protein across meals rather than loading it into one is supported, and the current Dietary Guidelines put it in a section headed "Prioritize Protein Foods at Every Meal". What is not settled is the per-meal number. The ACSM joint position statement points to roughly 0.25–0.3 g/kg or 15–25 grams per occasion; the ISSN position stand points to 0.25 g/kg or 20–40 grams every three to four hours. Those do not agree.

Because of that, the per-occasion figure here is your daily total divided by the number of occasions you enter. It is a planning split, not a physiological threshold.

Assumptions and limitations

• It uses the weight you type. No ideal weight, goal weight or lean mass is substituted behind your back.
• Ranges are population figures. They come from guidance and pooled research about groups of people. Individual needs vary, and none of these sources claims otherwise.
• Age, sex and height are not collected. None of them changes a grams-per-kilogram recommendation, so asking for them would add friction without changing the answer.
• Protein quality and source are not modelled. Total grams is the question here.
• This is a general adult nutrition estimate, not a medical nutrition prescription.

Who should not use this calculator on its own

Protein needs in these situations are individual, and some of them involve deliberately limiting protein under supervision. A general formula can produce a number that is actively wrong. Please work from advice given to you by a clinician or registered dietitian rather than from this page:

• Children and anyone under 18
• Pregnancy
• Breastfeeding
• Chronic kidney disease not on dialysis, where protein is often restricted
• Anyone on dialysis, where needs are usually higher and are prescribed
• Liver disease
• A current or past eating disorder
• Any medically prescribed diet — the prescription overrides this calculator

Sources, assumptions, and review

Every number this calculator publishes comes from one of the following. Each is linked to the specific figure it supports.

• Adult RDA, 0.8 g/kg — National Academies, Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2005). A minimum-requirement reference from nitrogen-balance data.
• Protein serving goal, 1.2–1.6 g/kg — Dietary Guidelines for Americans 2025-2030, which states: "Protein serving goals: 1.2–1.6 grams of protein per kilogram of body weight per day, adjusting as needed based on your individual caloric requirements."
• The disagreement about that goal — the American Society for Nutrition published a Perspective arguing the evidence does not yet justify applying a higher-protein recommendation to every adult across the lifespan. That view is not settled either way, and you should know it exists.
• Athlete range 1.2–2.0 g/kg, energy restriction, and per-meal figures — Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM, Nutrition and Athletic Performance (2016).
• 1.4–2.0 g/kg for exercising adults, and per-meal dosing — International Society of Sports Nutrition position stand: protein and exercise (2017).
• The 1.62 g/kg plateau for muscle gain — Morton et al. (2018), British Journal of Sports Medicine, a systematic review and meta-regression of 49 studies.

This calculator provides a general adult nutrition estimate, not a medical nutrition prescription. It has not been reviewed by a physician or a dietitian, and it does not claim to have been. What it does instead is show you every source behind every number, so you can check the reasoning yourself or take it to someone who can.

Related calculators

• Macro calculator — split a daily calorie target across protein, carbohydrate and fat.
• TDEE calculator — estimate the daily energy expenditure your calorie target sits inside.
• Calorie deficit calculator — size a deficit if weight loss is the goal.
• Lean body mass calculator — estimate lean mass if you want a different basis for your target.
• All health calculators.