A boneless, skinless chicken breast contains about 22.7 grams of protein per 100 grams when raw. Cooked, that number concentrates to roughly 31 grams per 100 grams because moisture evaporates during cooking. A standard 3-ounce (84-gram) serving of roasted chicken breast delivers 26 grams of protein and just 170 calories, according to USDA data.
Protein by Serving Size
Most nutrition labels and meal plans reference a 3-ounce cooked portion, but an actual chicken breast from the grocery store is almost always larger than that. A typical commercially sold breast weighs between 6 and 8 ounces raw, which shrinks to roughly 5 to 6 ounces after cooking. That means a single cooked breast usually delivers somewhere between 40 and 50 grams of protein, not the 26 grams you see on standardized charts.
Here’s a quick reference for cooked, boneless, skinless chicken breast:
- 3 oz (85 g): ~26 g protein, 170 calories
- 4 oz (113 g): ~35 g protein, 225 calories
- 6 oz (170 g): ~52 g protein, 340 calories
- 8 oz (227 g): ~70 g protein, 450 calories
If you’re tracking protein for fitness or weight management, weighing your chicken after cooking gives you the most accurate count. Raw weight and cooked weight are not interchangeable in a food log.
Why Chicken Breast Is So Protein-Dense
Raw chicken breast is roughly 75% water, 23% protein, and only about 2.6% fat, with essentially zero carbohydrates. That composition means the overwhelming majority of its calories come from protein. In a 3-ounce roasted serving, protein accounts for about 104 of the 170 total calories, or around 61%. Very few whole foods hit that ratio. This is the main reason chicken breast shows up in nearly every high-protein diet plan, from bodybuilding cuts to post-surgical recovery meals.
The protein in chicken breast is also “complete,” meaning it contains all nine essential amino acids your body can’t manufacture on its own. It’s particularly rich in leucine, the amino acid most directly involved in triggering muscle protein synthesis. That makes it especially useful after strength training, when your muscles are primed to absorb and use amino acids for repair.
How Cooking Affects the Numbers
Cooking does not destroy the protein in chicken breast. What changes is the weight of the meat itself. Roasting, grilling, and pan-searing all cause water to evaporate, which is why a 6-ounce raw breast might weigh only 4.5 ounces after cooking. The total grams of protein stay essentially the same, but the protein per gram of cooked meat goes up because the water is gone. Boiling and poaching retain slightly more moisture, so the cooked weight stays closer to the raw weight.
The practical takeaway: if a recipe or meal plan says “4 oz chicken breast,” check whether it means raw or cooked. Getting this wrong can throw your protein estimate off by 20% or more.
Chicken Breast vs. Thigh
Chicken thighs are a solid protein source, but the numbers aren’t identical. A 3-ounce skinless breast has about 140 calories and 3 grams of fat. The same portion of skinless thigh has 170 calories and 9 grams of fat, with triple the saturated fat. Both cuts deliver a similar amount of protein per serving, but breast meat gets you there with significantly fewer calories and less fat.
If you’re eating chicken purely for protein efficiency, breast wins. If you’re less concerned about fat and want more flavor and tenderness (thigh meat is harder to overcook), thighs are a perfectly reasonable choice. The protein difference between the two is small enough that preference and cooking style can be the deciding factor for most people.
How Much of Your Daily Protein One Breast Covers
The baseline recommendation for protein is 0.36 grams per pound of body weight per day. For a 150-pound person, that works out to about 54 grams. A single average-sized cooked chicken breast (around 6 ounces) would cover nearly all of that in one meal. For a 180-pound person, the minimum is about 65 grams, still largely covered by one breast.
Those minimums are set to prevent deficiency, not to optimize body composition. People who exercise regularly, are trying to lose weight while preserving muscle, or are over 65 generally benefit from higher intakes, often in the range of 0.6 to 1.0 grams per pound. At those levels, a 170-pound active person might aim for 100 to 170 grams of protein daily. Two chicken breasts would supply roughly 80 to 100 grams of that target, leaving room for other protein sources throughout the day.
The Dietary Guidelines for Americans recommend 5.5 to 7 ounce-equivalents of protein foods per day for adults, depending on calorie needs. One chicken breast alone often meets or exceeds that guideline, which is one reason it remains the default protein source for anyone trying to hit a high target without excess calories.