Tofu is a low-calorie protein source, coming in at roughly 114 calories per 100 grams for firm varieties. That’s about 30% fewer calories than skinless chicken breast (165 calories per 100g) and a fraction of what you’d get from cheese, nuts, or most other protein-rich foods. The exact count depends on the type of tofu and how you prepare it.
Calories by Tofu Type
Not all tofu is created equal. The more water a block of tofu contains, the fewer calories it has. Silken tofu, which has the highest water content, is the lightest option. A single slice (about 84 grams) of silken firm tofu contains just 52 calories. Regular firm tofu, the kind most people buy for stir-fries and scrambles, runs about 144 calories per half cup (126 grams). Extra-firm tofu is slightly denser still, though the difference from regular firm is modest.
For practical purposes, a half-cup serving of firm tofu gives you 144 calories, nearly 15 grams of protein, about 11 grams of fat (only 1.6 grams saturated), and just 2.5 grams of net carbohydrates after subtracting fiber. That combination of high protein, low carbs, and moderate fat makes tofu unusually nutrient-dense for its calorie count.
How Tofu Compares to Other Proteins
Gram for gram, tofu delivers fewer calories than almost every common protein source. At 114 calories per 100 grams, it undercuts chicken breast (165 calories), lean ground beef (around 250 calories), salmon (208 calories), and eggs (155 calories). The tradeoff is protein density: chicken breast packs 31 grams of protein per 100 grams compared to tofu’s 12 grams. So while tofu is lower in calories, you need a larger portion to match the protein content of meat.
That said, soy protein keeps you just as full as animal protein. A study published in The Journal of Nutrition found that when people ate meals matched for protein and fiber, soy and beef produced virtually identical effects on hunger, fullness, and how much food people ate at their next meal. Participants requested dinner at about the same time (roughly four hours later) and consumed the same number of calories afterward, regardless of which protein they’d eaten.
Why Preparation Method Matters
Plain tofu is low calorie. The way you cook it can change that quickly. A half cup of raw firm tofu at 144 calories can easily double when deep-fried, because tofu’s porous texture absorbs oil like a sponge. Pan-frying with a tablespoon of oil adds roughly 120 calories to the pan, and tofu will soak up a good portion of it.
Pre-marinated and pre-seasoned tofu products from the grocery store also run higher. A 4-ounce serving of herb-marinated seared tofu, for example, hits 205 calories, largely because of the oil used in preparation. That’s still reasonable, but it’s a meaningful jump from plain tofu.
If you’re watching calories closely, the lightest cooking methods are baking, grilling, air-frying, or adding cubed tofu directly to soups and stews. Pressing firm tofu before cooking removes excess water and improves texture without adding any calories. A light coating of cooking spray rather than a pool of oil in the pan keeps things closer to tofu’s baseline calorie count.
What Else You Get Per Calorie
Tofu’s calorie efficiency goes beyond just protein. Firm tofu prepared with calcium sulfate (the most common setting agent) is a strong source of calcium, which is why it shows up in so many plant-based diet recommendations. It also provides iron and contains nearly 3 grams of fiber per cup, something animal proteins don’t offer at all. With only 1.6 grams of saturated fat per cup, it fits easily into heart-healthy eating patterns.
The net carbohydrate count is particularly low. After subtracting fiber, a full cup of firm tofu contains about 2.5 grams of net carbs. That makes it compatible with low-carb and ketogenic diets, where many other plant-based protein sources (beans, lentils, quinoa) are too carb-heavy to use freely.
Keeping Tofu Low Calorie in Practice
The simplest way to keep tofu in the low-calorie category is to start with plain, unflavored blocks and season them yourself. Soy sauce, rice vinegar, garlic, ginger, chili flakes, and nutritional yeast all add flavor with minimal calories. Marinating tofu for 30 minutes before baking or air-frying gives you the taste of restaurant-style preparations without the added oil.
Silken tofu is worth keeping in mind if you’re looking for the absolute lowest calorie option. It blends smoothly into smoothies, salad dressings, and sauces, adding protein and creaminess at roughly 60 calories per 100 grams. It also works as a base for desserts like chocolate mousse, replacing higher-calorie ingredients like cream or avocado.
For meals where tofu is the main protein, a full cup of firm tofu (about 250 grams) provides roughly 30 grams of protein for under 300 calories. Pair that with vegetables and a whole grain, and you have a complete meal that’s filling, balanced, and well under 500 calories total.