Watching carbohydrates doesn't mean giving up soy foods. Tofu, tempeh, and edamame can fit into low-carb and ketogenic meal plans — but their net carb counts are not identical. This Soy Net Carbs Calculator does the math for you: pick a soy food, enter your serving size in grams or ounces, and see total carbohydrates, fiber, and the resulting net carbs instantly.
Net carbs are the carbohydrates your body actually absorbs and can use for energy. Because fiber is not digested like other carbs, it is subtracted from the total. The same applies to sugar alcohols when relevant. This calculator uses standard USDA-style values for common soy foods, and you can switch to custom values if you are using a product label from a specific brand.
Designed for keto dieters, diabetics, macro trackers, and anyone curious about plant-based nutrition, this tool delivers clear numbers in seconds.
🥢 Soy Net Carbs Calculator
Estimate digestible carbs in tofu, tempeh, edamame, and other soy foods.
📊 Net Carbs Result
Quick Start
This calculator works with the most common soy foods. Pick a food from the dropdown, enter a serving size in grams or ounces, set the number of servings, and click Calculate Net Carbs.
- Choose a preset soy food or toggle custom nutrition values.
- Weigh your actual portion — a kitchen scale gives the most accurate macros.
- Use the 28 g, 50 g, 100 g, or 155 g quick buttons for common portions.
- Switch to ounces if your recipe or food scale uses imperial units.
If you are tracking a specific product, use the custom fields and enter the values printed on the label as grams per 100 g.
How Net Carbs Work
Net carbohydrates represent the carbs your body actually digests and absorbs. Fiber resists digestion, so it is subtracted from total carbohydrates. Sugar alcohols are only partially absorbed, so they are also subtracted when a product contains them.
Net carbs = total carbohydrates − fiber − sugar alcohols
Worked example: 100 g of shelled edamame contains about 8.9 g total carbs and 5.2 g fiber. Net carbs = 8.9 − 5.2 = 3.7 g per 100 g. In a 155 g cup, that works out to about 5.7 g net carbs.
Reference Values
Values below are approximate, based on USDA FoodData Central data for cooked or prepared products. Individual brands can differ, so check the label when precision matters.
| Food | Total carbs (g/100g) | Fiber (g/100g) | Net carbs (g/100g) |
|---|---|---|---|
| Edamame, shelled, cooked | 8.9 | 5.2 | 3.7 |
| Firm tofu | 4.2 | 1.9 | 2.3 |
| Soft / silken tofu | 3.3 | 0.2 | 3.1 |
| Tempeh | 7.6 | 5.0 | 2.6 |
| Unsweetened soy milk | 1.7 | 0.6 | 1.1 |
| Roasted soy nuts | 33.0 | 17.0 | 16.0 |
| Textured vegetable protein, dry | 34.0 | 16.0 | 18.0 |
Tips & Best Practices
Weigh your food in its prepared form. A label may mention one serving, but the carb and fiber values in this calculator are based on 100 grams, so a scale keeps your macros honest.
- For marinated, battered, or flavored soy foods, use the custom fields and enter the values from the package label.
- If the label lists sugar alcohols but no separate fiber row, subtract both from total carbs.
- Net carbs do not tell the whole blood-sugar story; if you manage diabetes, consider testing your own glucose response.
Common Mistakes to Avoid
Do not subtract fiber twice. Some food databases list available carbs after fiber has already been removed; in that case, use the available carb number directly as your net carb base.
- Forgetting to convert ounces to grams before multiplying the per-100-g values.
- Using dry values for rehydrated textured vegetable protein.
- Ignoring added sugars or starches in sweetened soy milk and flavored soy yogurt.
Frequently Asked Questions
Is tofu good for keto? Firm tofu is a common keto staple — roughly 2.3 g net carbs per 100 g, along with plant protein and a modest amount of fat.
Why does my package label disagree with the preset values? Manufacturers can fortify, flavor, or process products differently. Added fibers, gums, and sugars all change the total carbohydrate and fiber numbers, so use custom values for exact tracking.
Can a soy food have calories even when net carbs are low? Yes. Net carbs only describe digestible carbohydrates. Fiber can still contribute some calories through fermentation, and protein and fat supply most of the energy in many soy foods.
Additional Resources
- USDA FoodData Central — search official nutrition data for raw, cooked, and packaged soy products.
- Net carbohydrate (Wikipedia) — background on fiber, sugar alcohols, and the reasoning behind the net carb equation.