Firm vs Extra-Firm vs Silken

How much protein is in tofu? For the USDA references in this calculator, protein per 100g spans about 4.8g (silken soft) to 10.0g (extra-firm block). Silken Mori-Nu products list 4.8–6.9g; refrigerated firm block lists 9.0g; extra-firm lists 10.0g [1][2][3][4].

Some summaries quote 10–17g for firm tofu. The upper end usually comes from a separate drier raw firm USDA record (~17g / 100g, FDC #172475) — not the same food state as typical water-packed block tofu (~9g / 100g, FDC #172448). Match the reference to what you actually log.

These are separate reference records, not interchangeable averages. Select the tofu type in the calculator before logging a portion.

Block Weight Varies — Weigh or Check Your Package

Refrigerated tofu blocks commonly range from about 14 oz (396g) to 16 oz (454g), but package sizes differ by brand and market. Do not assume one block weight for all products. Our block portion presets use a 396g reference block — adjust in the calculator if your package lists a different net weight.

At firm tofu values (9.0g protein / 100g), half of a 396g block (~198g) provides about 17.8g protein and 154 kcal. A 16 oz (454g) block at the same reference would provide about 20.4g protein per half block (~227g).

Calcium-Set Tofu and Micronutrients

Firm and extra-firm USDA references include calcium coagulant data: firm tofu lists 201mg calcium per 100g; extra-firm lists 282mg per 100g (FDC #172448, #174290). Silken Mori-Nu references list much lower calcium (31–32mg per 100g) because they represent different product formulations [1][2].

Iron varies similarly: extra-firm lists 2.0mg per 100g vs silken soft at 0.8mg. For accurate micronutrient logging, use the variant that matches your product type — or your package Nutrition Facts label for branded items.

Tofu Nutrition by Type (per 100g, USDA references)

NutrientFirmExtra-FirmSilken Soft (Mori-Nu)Silken Firm (Mori-Nu)
Protein (g)9.010.04.86.9
Calories (kcal)78835562
Total Fat (g)4.25.32.72.7
Carbohydrates (g)2.91.22.92.4
Calcium (mg)2012823132
Iron (mg)1.62.00.81.0
Sodium (mg)124536

Practical Tips for Tofu

  • 1

    Select firmness before logging — firm, extra-firm, and silken tofu use different USDA reference records with meaningfully different protein per 100g.

  • 2

    Weigh tofu in grams rather than assuming block fractions without checking package net weight.

  • 3

    Check your package label for branded tofu — generic USDA references may not match a specific product's Nutrition Facts panel.

  • 4

    Log cooking oil separately — pan-frying adds fat and calories not included in plain tofu base values.

  • 5

    Silken Mori-Nu rows are branded references — other silken products may differ; use your label when available.

Frequently Asked Questions — Tofu

How many calories are in 100g of firm tofu?
USDA firm tofu (FDC #172448) lists 78 calories, 9.0g protein, 4.2g fat, and 2.9g carbohydrates per 100g.
Does extra-firm tofu have more protein than firm tofu?
Per 100g, extra-firm tofu (FDC #174290) lists 10.0g protein vs 9.0g for firm tofu (FDC #172448). The difference reflects lower water content in extra-firm products, not additional soy protein.
How much protein is in half a block of tofu?
It depends on block weight and tofu type. For a 396g reference block of firm tofu, half (~198g) provides about 17.8g protein. Check your package net weight and use the block portion calculator for your specific block size.
Is silken tofu lower in protein than firm tofu?
Yes, per USDA references. Mori-Nu silken soft lists 4.8g protein per 100g vs 9.0g for generic firm tofu. Silken products retain more water, which dilutes protein per 100g.

Important Notice

Nutritional values are based on USDA FoodData Central reference entries for specific tofu types (FDC #172448, #174290, #174292, #172461). Block portion presets use a 396g reference weight — actual package sizes vary. Branded product labels are the most accurate source for a specific item. This tool is for nutrition journaling only — not medical advice.

About the Author

Manish Kumar - Author
Manish KumarNASM Certified Personal Trainer (CPT)

Certified fitness professional and nutrition researcher with over 10 years of experience in the fitness and wellness industry. Founder of Food Nutrify, dedicated to making accurate, science-backed nutrition data accessible to everyone through free, easy-to-use calculators.

NASM Certified Personal TrainerSports Nutrition Specialist

References & Sources

  1. [1] USDA FoodData Central (2024). Tofu, firm, prepared with calcium sulfate and magnesium chloride (nigari) — FDC #172448. U.S. Department of Agriculture, Agricultural Research Service.
  2. [2] USDA FoodData Central (2024). Tofu, extra firm, prepared with nigari — FDC #174290. U.S. Department of Agriculture, Agricultural Research Service.
  3. [3] USDA FoodData Central (2024). MORI-NU, Tofu, silken, soft — FDC #174292. U.S. Department of Agriculture, Agricultural Research Service.
  4. [4] USDA FoodData Central (2024). MORI-NU, Tofu, silken, firm — FDC #172461. U.S. Department of Agriculture, Agricultural Research Service.
  5. [5] USDA FoodData Central (2024). Tofu, raw, firm, prepared with calcium sulfate — FDC #172475 (higher-density raw firm reference). U.S. Department of Agriculture, Agricultural Research Service.