How this calculator works
This calculator scales a daily protein target from your body weight and how active you are. The baseline is the official Recommended Dietary Allowance (RDA) of 0.8 grams per kilogram of body weight, which is set to prevent deficiency in a sedentary adult, not to optimize performance or muscle growth.
For people training regularly, sports-nutrition sources commonly cite higher ranges: roughly 1.2 to 1.4 g/kg for endurance exercise and up to about 2.2 g/kg for those focused on building or preserving muscle. These are widely cited ranges from sports-nutrition literature, not official dietary allowances, and individual needs vary with training volume, age and overall calorie intake. These figures are general estimates, not medical advice.
The formula
Daily protein (g) = body weight (kg) × grams per kilogram for your goalPer-meal protein (g) = daily protein ÷ number of meals0.8 g/kg is the RDA baseline for sedentary adults. 1.2-1.4 g/kg (endurance) and 1.4-2.2 g/kg (muscle building/strength) are commonly cited sports-nutrition ranges, not official allowances.
Worked example: 70 kg, building muscle, 4 meals
- Range for building muscle: 1.4 to 2.2 g per kg of body weight.
- Low end: 70 × 1.4 = 98 g/day. High end: 70 × 2.2 = 154 g/day.
- Split across 4 meals: 98 ÷ 4 = 24.5 g and 154 ÷ 4 = 38.5 g per meal.
- Result: about 98-154 g/day, roughly 25-39 g per meal.
Frequently asked questions
Is the RDA of 0.8 g/kg enough for someone who exercises?
The RDA is set to prevent deficiency in a mostly sedentary adult, with a safety margin built in for most people. It does not target optimal muscle repair or growth, which is why sports-nutrition guidance recommends higher intakes for people training regularly.
Can eating more protein than I need build more muscle?
No. Beyond a certain intake, roughly in the upper part of the ranges shown here, additional protein does not meaningfully speed muscle growth and is simply used for energy or excreted. Training stimulus and total calories matter more once you're within the commonly cited range.
Should protein needs go up during a calorie deficit?
Many sports-nutrition sources suggest leaning toward the higher end of these ranges while cutting calories, since adequate protein helps preserve lean mass during weight loss.
Why split protein across several meals instead of one big serving?
Spreading intake across 3-5 meals is a common practical strategy so muscle protein synthesis is stimulated repeatedly through the day, rather than trying to eat one very large amount at once.
Does body weight or lean body mass matter more for this calculation?
Most published guidelines, including the ranges used here, are expressed per kilogram of total body weight for simplicity. Athletes with a lot of body fat sometimes use lean body mass instead to avoid overestimating needs.