A typical 14-ounce block of firm tofu holds about 65–70 grams of protein, but the exact amount depends on block weight, firmness, and brand.
Tofu looks simple on the plate, yet the protein math behind a full block can feel a bit vague. Packages list grams per serving, blocks come in different sizes, and brands use their own serving cuts. When you try to track intake, one basic question comes up right away: how many grams of protein in a block of tofu are you actually eating?
The good news is that once you know two things—the weight of the block and the protein per 100 grams—you can get a solid estimate in seconds. Most firm tofu sits around 15–18 grams of protein per 100 grams of weight, based on datasets that pull from firm tofu nutrition data. From there, a common store block in the 350–400 gram range ends up with roughly 55–70 grams of protein for the whole piece.
How Many Grams Of Protein In A Block Of Tofu?
When you ask “How Many Grams Of Protein In A Block Of Tofu?”, the short answer is that a full block usually falls into a broad band rather than a single fixed number. There is no worldwide standard block size. Brands sell blocks anywhere from about 250 grams up to 450 grams, and softer styles hold more water and less protein per gram than firm or extra firm styles.
A useful way to think about it is by pairing typical block weights with average protein density. Firm tofu made with calcium sulfate often lands close to 17 grams of protein per 100 grams. Soft or silken tofu can drop closer to 4–8 grams per 100 grams. That means two blocks that look similar on the shelf can end up with very different totals if one is dense and the other is delicate and wobbly.
| Block Size (Approx Weight) | Typical Firmness | Approx Protein In Whole Block |
|---|---|---|
| 250 g (about 9 oz) | Soft / Silken | 10–20 g |
| 300 g (about 10.5 oz) | Soft / Medium | 20–30 g |
| 340 g (12 oz) | Medium / Firm | 40–55 g |
| 350 g (about 12.3 oz) | Firm | 50–60 g |
| 396 g (14 oz, very common) | Firm / Extra Firm | 65–70 g |
| 400 g (about 14.1 oz) | Firm / Extra Firm | 65–72 g |
| 450 g (about 16 oz) | Firm Family Block | 75–80 g |
For a rough rule of thumb, a small soft block might only match the protein in one or two chicken thighs, while a dense 14-ounce firm block can cover a full day’s protein for a lighter, less active adult. Exact numbers still come down to the label on the pack, but this range helps you sanity-check any claim that seems oddly low or unrealistically high.
Protein Grams In A Block Of Tofu By Weight
If you want a clearer answer than a loose range, you can run a quick three-step check using the numbers on the label. This works whether you are counting macros for strength training, tracking plant protein on a new diet pattern, or just planning how many meals you can stretch from a single pack.
Step 1: Check The Block Weight On The Package
Start by finding the total weight on the front or back of the pack. In many regions, blocks land between 300 and 400 grams. Some are listed in ounces only, such as 12 oz or 14 oz. If that is the case, you can convert by multiplying ounces by 28.35 to get grams. So a 14-ounce block ends up at about 397 grams, which most labels round to 396 or 400 grams.
Because brands cut slightly different block shapes, the exact gram number may not match the examples in this article, and that is fine. You just need a ballpark that is close enough to run protein math based on grams per 100 grams or grams per serving.
Step 2: Look At Protein Per 100 Grams Or Per Serving
Next, find the part of the label that lists protein per serving, plus the serving size. Firm tofu often shows something like “Protein: 16 g” for a 100 gram serving or “Protein: 8 g” for a half-serving of 50 grams. Databases that draw from standardized lab work put firm tofu around 15–18 g of protein per 100 g, while soft tofu often sits in the 7–9 g range and very silky styles can drop toward 4–6 g per 100 g.
On many packages, the serving is not 100 grams. It might be “3 oz” or “1/5 block”. In that case, you can still scale it up. If a 3-ounce serving (about 85 g) of firm tofu lists 14 g of protein, that is roughly 16–17 g per 100 g. That number becomes your base for the rest of the block.
Step 3: Do A Quick Block Protein Estimate
Once you have block weight and protein per 100 g, the estimate is straightforward. Multiply the block weight by protein per gram. A handy way to do it in your head is to think in “hundreds of grams.” For a 400 g block of firm tofu at 17 g of protein per 100 g, take 17 and multiply by four. That gives you about 68 g of protein in the full block.
Here is another example that matches a lighter block. A 300 g block of medium tofu at 10 g of protein per 100 g works out to three times 10, or 30 g of protein in the full piece. That may be perfect for one high-protein dinner or two moderate plates with plenty of other sides.
If the label only shows protein per serving and servings per pack, you can multiply those instead. A block with four servings at 13 g each adds up to 52 g for the pack. When you are reading How Many Grams Of Protein In A Block Of Tofu? style questions online, this little bit of math gives you the tools to check claims against what you see in your own kitchen.
Firm Vs Soft Tofu Protein By Block Type
Not all tofu styles give the same protein punch per block. Water content plays a big role. Firm and extra firm blocks have been pressed harder, so more water leaves the curds. That makes every gram of tofu denser in soy solids and raises the protein count. Soft, silken, and dessert tofu hold more water, so a full block can feel large but still deliver less protein than a smaller, denser block.
Firm And Extra Firm Blocks
Lab data on firm tofu prepared with calcium sulfate show that 100 g gives roughly 15–18 g of protein, with some brands a touch higher or lower. Extra firm tofu often lands in the same band or just above, as long as the block is not heavily flavored with extra oils or starches. A 350–400 g firm or extra firm block usually spans 55–70 g of protein once you run the math.
That density is one reason many plant-focused meal plans treat a block of firm tofu like a bag of chicken breasts. It is easy to cut into four equal slabs or cubes, cook them in different ways through the week, and stay somewhere near 13–18 g of protein per serving without much extra thought.
Soft And Silken Blocks
Soft tofu keeps more moisture and feels fragile in the pan, which also lowers protein per gram. Many lab reports place soft tofu around 7–9 g of protein per 100 g, while silken tofu made for soups or desserts can dip closer to 4–6 g per 100 g. A large 400 g silken block can still land under 30 g of protein in total.
That does not make soft or silken tofu a poor choice. These styles shine in smoothies, sauces, soups, and baked sweets where silky texture matters more than maximum density. You just need to know that “one block” here does not match “one block” of firm tofu once you compare total grams of protein.
Smoked, Baked, And Flavored Tofu
Smoked and baked tofu often start with firm blocks and then lose even more water during cooking or smoking. Seasonings add a bit of weight back, but many of these products still end up quite dense. A 200 g slab of baked tofu can rival a much larger plain block in total protein.
Flavored tofu that comes marinated in sauces may contain added sugars, oils, or starches. Those extras raise calories without always raising protein. In these cases, it helps to rely on the label rather than guess by sight, because a shiny glaze can hide a lower protein count than you would expect from the firm texture alone.
| Tofu Style | Protein Per 100 g (Approx) | Protein In 300 g Block (Approx) |
|---|---|---|
| Silken | 4–6 g | 12–18 g |
| Soft | 7–9 g | 21–27 g |
| Medium | 10–12 g | 30–36 g |
| Firm | 15–18 g | 45–54 g |
| Extra Firm | 16–20 g | 48–60 g |
| Baked / Smoked | 16–22 g | 48–66 g |
| High-Protein Specialty | 20–25 g | 60–75 g |
The ranges in this table reflect common values from nutrition databases and supermarket products. Your own pack might lean toward the low or high end, especially if it is fortified with extra soy protein or pressed more firmly than average. Always treat the label as the final word for that exact product.
How A Tofu Block Fits Into Daily Protein Needs
Knowing the protein in a block helps most when you can place it against your daily target. Many health bodies and nutrition writers base baseline needs for healthy adults on the Recommended Dietary Allowance of 0.8 g of protein per kilogram of body weight per day. A 70 kg person (about 154 pounds) would need around 56 g of protein each day under that guideline, though some people benefit from higher intake. Sources such as Harvard Health’s overview of protein needs explain how activity level, age, and goals change that number.
Now line that up with a typical block. A 400 g block of firm tofu at 17 g of protein per 100 g sits around 68 g of protein for the whole piece. For the 70 kg example, that single block covers the baseline daily target and leaves a small cushion. In real life, most people split a block across two to four meals, mixing tofu with beans, grains, dairy, eggs, or meat so that no single food has to carry the full load.
If your needs sit higher because you train hard, are recovering from injury, or follow advice from a clinician for a higher-protein pattern, tofu still scales well. Two medium firm blocks across a day can bring 90–120 g of protein before you even count side dishes. On days when appetite is lower, a soft or silken block in a smoothie or soup can at least keep a steady stream of amino acids coming in.
Practical Tofu Protein Takeaways
To wrap up, the phrase “block of tofu” hides a lot of variation. Block weight, water content, and brand all shift how many grams of protein you actually get. Most firm or extra firm blocks in the 350–400 g range land between 55 and 70 g of protein, while softer blocks of the same size drop closer to 20–35 g. A quick look at the label and a little arithmetic bridge that gap and turn a vague guess into a clear number.
If you treat “grams per 100 g” as your anchor, you can compare any tofu product against your own needs, swap between brands without stress, and decide whether one block feeds you for a full day or just for a single stir-fry. Once that habit sticks, the question How Many Grams Of Protein In A Block Of Tofu? changes from a puzzle into a quick mental check you can run every time you open the fridge.