Quick answer: chicken usually wins, but not by much

A typical cooked chicken breast is one of the highest-protein foods you can eat. USDA FoodData Central lists roasted chicken breast, meat only, at about 31 g of protein per 100 g. Many tuna products are close behind, but usually a bit lower; for example, canned tuna in water, drained, is commonly around 25–29 g of protein per 100 g depending on the type.

So if you compare equal weights, chicken breast is generally higher in protein than tuna. If you compare a whole can of tuna to a smaller chicken portion, however, tuna may end up giving you more total protein for that meal.

Why the numbers change so much

The protein total depends on more than just the animal. Tuna varies by species and preparation: light tuna, albacore tuna, fresh tuna steaks, and canned tuna all have slightly different nutrition profiles. Chicken also changes based on the cut and whether the skin is included. Skinless breast is leanest and highest in protein per calorie; thigh and wing meat usually have a bit less protein per gram and more fat.

Cooking method matters too because water loss concentrates nutrients. That means cooked weights often look higher in protein per 100 g than raw weights, even though the total protein in the original piece of meat has not magically increased.

Protein quality, calories, and what matters for your goals

Both tuna and chicken are complete proteins, meaning they provide all essential amino acids. For muscle building, fat loss, or simply meeting daily protein needs, either can be an excellent choice.

If you want the most protein for the fewest calories, skinless chicken breast is hard to beat. Tuna is also very efficient, but it often brings a bit less protein per 100 g and may come with more sodium if canned. Tuna has another tradeoff: because some tuna can be higher in mercury, it’s smart to follow FDA and EPA guidance on how often you eat certain types, especially for pregnant people and young children.

Best way to choose between tuna and chicken

Pick chicken breast when you want the highest protein density and a versatile base for meals. Pick tuna when you want convenience, a no-cook protein source, or a different flavor profile. Neither is universally better; the best option is the one that fits your schedule, appetite, and overall diet.

If you’re tracking macros, the big practical difference is usually portion size rather than the food itself. A 4-ounce serving of either food can provide roughly 25–35 g of protein, which is enough to make a strong protein-focused meal.

Tips

• Compare equal cooked weights, not just “one can” vs “one piece,” to get a fair protein comparison.
• Choose skinless chicken breast if your goal is the most protein with the least fat.
• If using tuna often, vary the type and follow mercury guidance, especially for pregnancy or kids.
• Use a kitchen scale or nutrition app so portion sizes match your macro target.
• Pair either protein with vegetables and a carb source to make the meal more balanced and satisfying.