Protein Per Serving Calculator
Knowing the protein content of different foods helps you plan meals that meet your daily protein goals. This calculator uses protein density values (grams of protein per 100 g of food) from USDA FoodData Central, the authoritative source for US food composition data. Enter the food type, the weight of your serving in grams, and the calculator instantly shows the protein in that serving plus the percentage of the FDA daily value (50 g). A lookup table covers 12 common high-protein foods. For precise values on any food not listed, look up the food directly in USDA FoodData Central at fdc.nal.usda.gov and enter the protein per 100 g manually.
Protein calculation formula
Protein (g) = serving_weight (g) * protein_per_100g / 100
% Daily Value = protein (g) / 50 * 100
FDA Daily Value for protein: 50 g/day (for 2,000 kcal/day reference diet)
USDA DRI for protein: 0.8 g per kg body weight per day (sedentary adults)
High-protein food tips
- Chicken breast, lean beef, fish, and eggs are among the most protein-dense foods per gram.
- Legumes (lentils, beans, chickpeas) provide 7-9 g protein per 100 g cooked - excellent for plant-based diets.
- Greek yogurt and cottage cheese deliver 10-11 g protein per 100 g with minimal fat when low-fat versions are chosen.
- Spreading protein across 3-4 meals supports muscle protein synthesis better than consuming all protein in one meal.
- For most adults, hitting 25-40 g protein per meal is a practical target that meets daily needs across 3 meals.
Protein per serving: frequently asked questions
How much protein per day do adults need?
The USDA Dietary Reference Intake (DRI) for protein is 0.8 grams per kilogram of body weight per day for sedentary adults. For a 70 kg (154 lb) adult, that is 56 g per day. Athletes, older adults, and pregnant or breastfeeding women typically need more: 1.2-2.0 g/kg/day depending on activity level.
How many grams of protein are in common foods per 100 g?
USDA FoodData Central values (per 100 g edible portion): chicken breast cooked 31 g, beef lean 26 g, salmon cooked 25 g, eggs whole 13 g, Greek yogurt 10 g, cooked lentils 9 g, tofu firm 8 g, cooked black beans 9 g, whole milk 3.2 g, oatmeal cooked 2.4 g.
How do I track protein intake across meals?
Track grams of protein per serving and add them up across all meals and snacks. Set a daily protein goal (your body weight in kg * 0.8 g as the minimum) and distribute it across meals. Aiming for 25-40 g protein per meal and 10-20 g per snack is a practical approach for most adults targeting adequate protein intake.
Is protein from plant sources as good as animal protein?
Plant proteins are generally lower in one or more essential amino acids compared to animal proteins. However, a varied plant-based diet that includes legumes, grains, nuts, and seeds across the day provides all essential amino acids. The Dietary Guidelines for Americans recognize both animal and plant proteins as part of a healthy dietary pattern.
What is the FDA Daily Value for protein?
The FDA sets the Daily Value for protein at 50 g per day for adults and children aged 4 and older, based on a 2,000-calorie diet. This is used on Nutrition Facts labels. Individual needs vary; 50 g/day is a reference point, not a universal recommendation.
Official sources
- USDA FoodData Central: FoodData Central - food composition data.
- FDA: Daily Value for Nutrition Facts Labels.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.