How much protein is in chicken breast? Per ounce, per 100g, per breast

Here is the short answer. Skinless, boneless chicken breast, raw carries 22.5 grams of protein per 100 grams, according to the USDA FoodData Central values in our index. Once it is cooked and roasted, the same meat measures 31 grams of protein per 100 grams. Cooking does not add protein. It removes water, so every gram of cooked breast is more concentrated than a gram of raw breast. Keep that raw versus cooked distinction in mind, because it explains most of the conflicting numbers you see online.

Protein per ounce

One ounce is 28.35 grams. Run the USDA per-100-gram values through that conversion and you get the per-ounce numbers most people are actually asking for:

• Raw chicken breast: about 6.4 grams of protein per ounce, with roughly 34 calories.
• Cooked, roasted chicken breast: about 8.8 grams of protein per ounce, with roughly 47 calories.

A practical rule of thumb for meal planning: figure 6 to 7 grams of protein per ounce if you weigh your chicken raw, and closer to 9 grams per ounce if you weigh it after cooking. If a recipe or tracking app does not say which state it means, that ambiguity alone can swing your protein estimate by 30 percent or more.

Protein per 100 grams

The 100 gram numbers come straight from the USDA reference data behind our food pages:

• Raw, skinless, boneless breast meat: 22.5 g protein, 120 calories, 2.6 g fat per 100 g.
• Roasted breast meat, meat only: 31 g protein, 165 calories, 3.6 g fat per 100 g.

Both versions are essentially carbohydrate free, and saturated fat stays around 1 gram or less per 100 grams. That combination, high protein, low fat, no carbs, is why chicken breast is the default protein anchor in so many American kitchens.

Protein per breast

There is no single official breast size, so treat these as USDA arithmetic applied to common weights. A modest boneless, skinless breast half weighing 4 ounces raw (113 grams) carries about 25 grams of protein and 136 calories. A larger 6 ounce raw breast (170 grams) carries about 38 grams of protein and 204 calories. Many supermarket breasts today run 8 ounces or more raw, which puts a single breast at roughly 51 grams of protein.

If you measure after cooking instead, the USDA lists a cup of chopped or diced roasted breast at 140 grams, which works out to about 43 grams of protein and 231 calories. However you slice it, one chicken breast covers a large share of a typical day's protein target. For what that target should actually be, see our guide on how much protein you need.

Protein per calorie: breast versus the alternatives

Raw numbers only tell half the story. The more useful comparison is protein per calorie, because it shows what your calorie budget is buying. Here is how the foods in our index compare per 100 calories:

• Chicken breast, roasted: about 18.8 g protein per 100 calories. Nutrient Density Score 71 cooked, 74 raw.
• Turkey, light meat, raw: about 20.8 g protein per 100 calories, at 23.7 g protein and 114 calories per 100 g. Score 75. Turkey breast meat edges out chicken breast on this measure.
• Chicken, stewing, meat only, raw: about 14.4 g protein per 100 calories. This whole-bird entry includes the darker cuts, and the extra fat (6.3 g per 100 g) is what drags the ratio down. Score 66.
• Chicken, ground, raw: about 12.2 g protein per 100 calories, since ground chicken typically blends in fattier meat. Score 59.
• Tofu, firm, prepared with calcium sulfate: about 12 g protein per 100 calories, at 17.3 g protein and 144 calories per 100 g. Its Nutrient Density Score of 88 beats every poultry entry here, because calcium-set tofu also delivers 683 mg of calcium plus iron and magnesium per 100 g.

The takeaway from that list: chicken breast and turkey breast are the leanest protein-per-calorie plays among these options, while tofu trades some protein efficiency for a much broader micronutrient package. Fattier chicken cuts land in between on protein but well below on density. For plant-forward swaps, our guide to protein without meat ranks the alternatives in detail.

Why the raw versus cooked mix-up matters

Meat loses roughly a quarter of its weight as water during roasting, which is why the USDA lists raw breast at 22.5 g protein per 100 g and roasted breast at 31 g. If you log 200 grams of raw chicken using cooked values, you will overestimate your protein by about 17 grams. Do the reverse and you will underestimate by the same margin. Pick one convention, raw weight or cooked weight, and stay consistent. Most packaged chicken lists raw values, so weighing raw is usually the simpler habit.

One last note on the score. Chicken breast rates 71 to 74 on our 1 to 100 Nutrient Density Score, solid but not elite, because the score measures total nutrition per calorie, not protein alone. Breast meat is a protein specialist. For the full picture of what it does and does not deliver, visit the roasted chicken breast food page.