A half-cup serving of firm tofu (about 126 grams) contains roughly 22 grams of protein. That makes it one of the most protein-dense plant foods available, comparable to a similar-sized portion of ground beef. The exact amount varies depending on the type of tofu you buy and how it’s prepared, but even the softest varieties deliver a meaningful amount of protein per serving.
Protein by Tofu Type
Tofu comes in a range of textures, and the firmer it is, the more protein it contains. That’s because firmer tofu has been pressed longer, squeezing out more water and concentrating the soy solids. Here’s what you can expect per 100 grams (about 3.5 ounces):
- Extra-firm tofu: 17 to 19 grams of protein
- Firm tofu: 17 grams of protein
- Soft tofu: 8 to 10 grams of protein
- Silken tofu: 5 to 6 grams of protein
If you’re eating a full cup of firm tofu (252 grams), you’re looking at about 43.5 grams of protein. That’s more than many people realize and enough to cover a large share of your daily needs in a single meal. The difference between silken and extra-firm is substantial, so if you’re choosing tofu specifically for protein, go with the firmest option you can find.
Tofu Is a Complete Protein
Unlike many plant proteins, tofu contains all nine essential amino acids your body can’t make on its own. It scores particularly well for phenylalanine (95% of the recommended daily intake per 100-gram serving), tryptophan (84%), and threonine (75%). Its lowest-scoring amino acid is methionine, at 29% per serving, which is common across legume-based proteins but still present in meaningful amounts.
When scientists measure protein quality using the PDCAAS scale (a score from 0 to 1 that accounts for both amino acid content and how well your body digests the protein), soy protein scores between 0.95 and 1.00. That puts it on par with eggs and dairy, and ahead of most other plant sources like lentils, rice, or nuts. You don’t need to combine tofu with grains or other foods to “complete” the protein. It’s already complete on its own.
How Cooking Affects Protein Content
Cooking tofu doesn’t destroy its protein. Heat causes the protein molecules to unfold and restructure, which changes the texture but doesn’t eliminate the amino acids. In fact, moderate cooking can actually improve how well your body absorbs the protein.
Frying tofu at moderate temperatures (up to about 150°C or 300°F for a few minutes) has been shown to improve its protein digestibility by reshaping the protein structure in a way that makes it easier for digestive enzymes to break down. Frying at very high temperatures for longer periods doesn’t offer the same benefit and can reduce digestibility somewhat. For most home cooking, a few minutes in a pan at medium-high heat is ideal.
Pressing tofu before cooking squeezes out water, which concentrates the remaining protein by weight. If you press a block of firm tofu for 20 to 30 minutes before cooking, the protein density per bite goes up simply because you’ve removed moisture. This is one reason baked or pan-fried tofu feels more satisfying than soft tofu straight from the package.
How Tofu Compares to Other Protein Sources
Per 100 grams, firm tofu’s 17 grams of protein puts it in a competitive range with many animal proteins, though it doesn’t quite match the density of chicken breast (about 31 grams per 100 grams) or lean beef (roughly 26 grams). It does outperform eggs (about 13 grams per 100 grams), most beans (7 to 9 grams per 100 grams cooked), and nearly all other soy products like tempeh’s close competitor edamame.
Where tofu stands out is calorie efficiency. A half-cup of firm tofu runs about 180 calories while delivering 22 grams of protein. It also brings along calcium when made with calcium sulfate (the most common coagulant), plus iron and small amounts of magnesium and zinc. You’re getting a nutrient-dense package, not just isolated protein.
How Much Tofu to Hit Your Protein Goals
Most adults need somewhere between 50 and 70 grams of protein per day, depending on body weight and activity level. A single cup of firm tofu (252 grams, or roughly half a standard block) delivers about 43.5 grams of protein, covering well over half that target in one sitting.
For context, a typical block of tofu sold in grocery stores weighs 350 to 400 grams. Eating half a block in a stir-fry or scramble gives you a protein load comparable to a large chicken breast. If you’re eating tofu across two meals in a day, you can comfortably reach your full protein target from tofu alone, though variety in your diet is always a good idea.
The FDA has recognized that consuming 25 grams or more of soy protein per day is associated with reduced risk of heart disease. That threshold is easy to hit with tofu. A single half-cup serving of firm tofu gets you nearly all the way there, and a full cup exceeds it by a wide margin.