How many carbs are in tofu?
A 3oz (84g) serving of firm tofu has about 0.8g of carbohydrate and essentially 0g of net carbs. It is one of the lowest-carb protein sources available.
Carbs by portion
| Portion | Total carbs | Fiber | Net carbs |
|---|---|---|---|
| 3oz firm tofu (84g) | 0.8g | 0.8g | 0.1g |
| 1 oz (56g) | 0.5g | 0.5g | 0.0g |
| 100 grams | 1.0g | 0.9g | 0.1g |
Net carbs
A 3oz serving of firm tofu has about 0.1g of net carbs, which is total carbs (0.8g) minus fiber (0.8g). The fiber almost entirely cancels the carbs. Even at 100g, tofu carries only 0.07g of net carbs. Silken tofu carries slightly more carbs than firm because it has higher water content relative to solid mass, but all plain tofu types are very low. See the net carbs guide.
For diabetes
Plain tofu is a safe, predictable protein for people managing blood sugar. The carb content is so low (under 1g per 3oz serving) that it has no meaningful effect on glucose. The main thing to watch is what tofu is cooked with: teriyaki glaze, sweet chili sauce, or honey-ginger marinades can add 5 to 15g of carbs per serving. Baked, pan-fried with soy sauce, or added to broth-based dishes keeps the carb count near zero. See the diabetes carb-counting guide.
Keto and low carb
Tofu fits keto easily. A 3oz serving has about 0.1g of net carbs, and even a large 200g block adds only about 0.1g of net carbs total. It is one of the few plant proteins that fits a strict 20g-per-day carb budget without any portion restriction. Pair it with olive oil, avocado, or full-fat sesame dressing to round out the macros.
Good to know
Firm and extra-firm tofu have the lowest carbs because more water has been pressed out, concentrating protein and lowering the carb-to-weight ratio. Silken tofu, used in smoothies and desserts, retains more water and registers slightly higher carbs per 100g. Flavored or pre-marinated tofu from the grocery store often has added sugar: check the label, because a teriyaki-marinated block can carry 6 to 10g of carbs per serving versus under 1g for plain.
Full nutrition (per 100g)
- Calories: 85.0 kcal
- Carbohydrate: 0.97g
- Fiber: 0.9g
- Sugars: 0.4g
- Protein: 10.92g
- Fat: 4.19g
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Get the appFrequently asked questions
How many carbs are in tofu?
A 3oz (84g) serving of firm tofu has about 0.8g of total carbs and roughly 0.1g of net carbs. Per 100g, that is 0.97g of carbs.
Is tofu keto?
Yes. Plain firm tofu has under 0.1g of net carbs per serving, which makes it one of the most keto-compatible plant proteins. Avoid flavored or marinated varieties with added sugar.
Does tofu raise blood sugar?
Plain tofu has almost no carbs, so it has no meaningful effect on blood sugar on its own. Marinades and sauces are the real variable to watch.
How does silken tofu compare to firm tofu in carbs?
Silken tofu has slightly more carbs per 100g than firm tofu because it retains more water and has a different texture, but both are very low. Firm tofu is denser, so a given weight carries more protein and proportionally less of everything else.
Is tofu a good protein source for low-carb diets?
Yes. Firm tofu has about 10.9g of protein per 100g and under 1g of carbs. It is one of the few complete plant proteins that fits both low-carb and keto diets without portion restriction.