Protein calculator: how many grams you need a day

Protein is the nutrient that varies most from person to person: the recommendation for a low-activity adult is a quarter of what is used in strength training. Getting it right avoids both falling short (muscle loss, poorer recovery) and overdoing it for no reason.

Enter your weight and pick your profile. You get the daily protein range in grams, the recommended figure (the midpoint) and how much to spread over each meal. Everything runs in your browser.

Protein is recommended in grams per kilo of body weight per day. For a healthy, low-activity adult, the official figure (WHO and FAO) is about 0.8 g/kg. For people who train, scientific society position stands raise it to between 1.4 and 2.0 g/kg, and a meta-analysis finds muscle gain stops rising, on average, near 1.6 g/kg. For people over 65 a little more is advised (1.0 to 1.2 g/kg) to slow muscle loss.

The calculator multiplies your weight by your profile’s range, gives the midpoint as the recommended figure and divides it by the number of meals. Each gram of protein supplies about 4 kcal.

How much protein you need

It depends on your weight, activity and age. The recommendation for a low-activity adult is about 0.8 g per kilo a day; for people who train, between 1.4 and 2.0 g/kg; for people over 65, between 1.0 and 1.2 g/kg.

Protein and muscle

To build muscle with strength training, evidence suggests that from about 1.6 g/kg the average benefit stops rising, although the individual range reaches 2.2 g/kg. If you are in a calorie deficit, the top of the range helps keep muscle mass.

How to spread it

Spreading protein over several meals (about 0.3 g/kg per meal, 20 to 40 g) seems to favour muscle protein synthesis more than concentrating it in one. The most important thing, in any case, is the day’s total.

Protein sources

Lean meat, fish, eggs, dairy, legumes, nuts, tofu, tempeh and wholegrains. Plant-based diets cover needs by combining different sources and, sometimes, a slightly larger amount.

Common mistakes

• Thinking more protein always gives more muscle: above about 2.2 g/kg there is no proven advantage.
• Calculating with total weight in cases of heavy overweight (a target weight can be used).
• Forgetting the protein in food when using shakes.
• Cutting protein when dieting.

Limits of this calculator

• These are general recommendations for healthy adults; they do not apply to children, pregnancy, breastfeeding or kidney or liver disease.
• It does not distinguish protein quality or source.
• The range is wide because of variability between people.

Notice

This is an estimate and does not replace advice from a doctor or dietitian. Consult a professional if you have a medical condition or follow a medical diet.