Beans are a staple of plant-based diets, prized for their protein and fiber, but their carbohydrate content varies widely by type and preparation. Whether you're tracking net carbs on a keto-style plan, managing blood sugar, or simply balancing your plate, knowing exactly how many carbs are in a 100-gram serving is essential. This calculator takes the guesswork out of your nutrition log.
Select from a database of common beans—from black beans and chickpeas to edamame and lentils—and instantly see total carbs, net carbs (after subtracting fiber), and the carb contribution from a custom portion size. You can also enter your own values if you have a specific product label. Perfect for meal preppers, dietitians, and anyone curious about the carbohydrate profile of their favorite legumes.
🥜 Bean Carb Calculator
How to Use This Tool
Start by selecting a bean type from the dropdown. The calculator uses standard USDA nutrition data for cooked beans (boiled, without salt) per 100 grams. If you're measuring a different portion, enter the weight in grams—the tool automatically scales the values. For a specific product or a bean not listed, choose "Custom" and enter the total carbs and fiber per 100g from the nutrition label.
Next, choose whether you want to see total carbs or net carbs. Net carbs are calculated by subtracting dietary fiber from total carbohydrates, a common approach for low-carb and ketogenic diets. Finally, click Calculate to see your results, including a full breakdown of carbs and fiber for both 100g and your custom portion.
How It Works
The calculator uses a simple proportional scaling formula. For a given bean, the carbohydrate content per 100g is multiplied by your portion weight divided by 100. For example, if black beans contain 23.7g of total carbs per 100g, a 150g serving would provide 23.7 × 1.5 = 35.6g of total carbs. The same logic applies to fiber and net carbs.
Net carbs are defined as total carbohydrates minus dietary fiber. Fiber is not digested like other carbs and has minimal impact on blood sugar, so many people subtract it when tracking carbs for glycemic control or ketosis. The formula is: Net Carbs = Total Carbs − Fiber.
All base values are sourced from the USDA FoodData Central database, which provides standardized nutritional information for cooked beans. These values can vary slightly by brand, cooking method, and whether salt or other ingredients are added.
Worked Examples
Example 1: You're making a chickpea salad and use 200g of cooked chickpeas. Chickpeas have 27.4g total carbs and 7.6g fiber per 100g. Total carbs in your portion: 27.4 × 2 = 54.8g. Net carbs: (27.4 − 7.6) × 2 = 19.8 × 2 = 39.6g.
Example 2: You're on a keto diet and want to keep net carbs under 20g per day. You eat 100g of edamame, which has only 8.9g total carbs and 5.2g fiber. Net carbs = 8.9 − 5.2 = 3.7g. That's a great low-carb choice compared to pinto beans (13.8g net carbs per 100g).
Tips & Best Practices
- Always weigh beans after cooking, as water absorption changes their carb density. Dry beans have roughly three times the carbs per 100g compared to cooked.
- If you're tracking for diabetes or insulin resistance, net carbs can be more useful than total carbs, but consult your healthcare provider for personalized advice.
- Rinsing canned beans can reduce sodium but does not significantly change carbohydrate content.
- For meal prep, calculate carbs per batch by multiplying the per-100g value by the total cooked weight and dividing by the number of servings.
Factors Affecting Accuracy
The values in this calculator are averages from the USDA database. Actual carb content can vary due to:
- Variety: Different cultivars of the same bean may have slightly different macronutrient profiles.
- Cooking method: Boiling, pressure cooking, or canning can affect water content and thus carb concentration per 100g.
- Added ingredients: Sauces, sugar, or fat in prepared bean dishes will alter the carb count.
- Measurement error: Weighing errors or using volume measurements instead of weight can lead to inaccuracies.
For the most precise tracking, use the nutrition label on your specific product and enter custom values.
Frequently Asked Questions
Are beans high in carbs? Yes, most beans are moderate to high in carbohydrates, but they also provide substantial fiber and protein. For example, 100g of cooked black beans has about 23.7g total carbs and 8.7g fiber, leaving 15g net carbs.
What beans are lowest in carbs? Edamame (green soybeans) is the lowest, with only 8.9g total carbs per 100g. Other lower-carb options include mung beans (19.2g) and lentils (20.1g).
Should I count net carbs or total carbs? It depends on your goals. For general health and diabetes management, total carbs are often used. For ketogenic diets, net carbs are more common because fiber doesn't raise blood sugar. Always follow the guidance of your dietitian or doctor.
Can I use this calculator for canned beans? Yes, but note that canned beans are typically cooked and have similar carb values to boiled beans. Check the label for any added sugar or starch.
Why do dry beans have more carbs per 100g? Dry beans contain very little water, so the same weight has more concentrated nutrients. When cooked, beans absorb water, so the carb content per 100g drops. Always use cooked values for portion tracking.
Additional Resources
For more detailed nutritional data, visit the USDA FoodData Central database. You can also explore our bean protein calculator to track protein alongside carbs, or use the avocado carb calculator for another low-carb plant food.