Net Carb Calculator – Track Net Carbohydrates for Keto
Calculate net carbohydrates by subtracting fiber and sugar alcohols from total carbs. Essential for keto, low-carb, and diabetic diets. Track multiple foods to manage your daily net carb intake.
How to Use This Net Carb Calculator
Follow these steps to calculate the net carbohydrates in your food:
- Optionally enter the food name for tracking purposes.
- Enter the total carbohydrates in grams (check the nutrition label).
- Enter the dietary fiber in grams.
- Enter any sugar alcohols in grams (common in sugar-free products).
- Click "Add Another Food" to track multiple items in one session.
- Click "Calculate Net Carbs" to see your total net carbs and keto assessment.
Net Carbs Formula
Net carbohydrates represent the carbs your body actually digests and absorbs. Fiber and sugar alcohols are subtracted because they have minimal impact on blood sugar:
This is why net carbs matter more than total carbs for low-carb and keto diets. Your body cannot fully digest fiber, so it passes through without spiking blood glucose. Sugar alcohols (erythritol, xylitol, etc.) are partially absorbed but have a significantly reduced glycemic impact.
Common Net Carb Examples
Total Carbs: 17g | Fiber: 7g | Sugar Alcohols: 0g
Net Carbs = 17 − 7 − 0 = 10g net carbs
Excellent keto-friendly food — high in healthy fats.
Total Carbs: 6g | Fiber: 3.5g | Sugar Alcohols: 0g
Net Carbs = 6 − 3.5 − 0 = 2.5g net carbs
Great low-carb snack for keto dieters.
Total Carbs: 22g | Fiber: 8g | Sugar Alcohols: 10g
Net Carbs = 22 − 8 − 10 = 4g net carbs
Despite 22g total carbs, only 4g net carbs — keto-friendly.
Frequently Asked Questions
What are net carbs?
Net carbs are the carbohydrates in food that your body actually digests and absorbs for energy. They are calculated by subtracting dietary fiber and sugar alcohols from total carbohydrates. Net carbs are the number most relevant for people following low-carb, keto, or diabetic diets because they represent the carbs that impact blood sugar levels.
Why do you subtract fiber?
Dietary fiber is a type of carbohydrate that the human body cannot fully digest. It passes through the digestive system largely intact and does not raise blood sugar or insulin levels. Since it has no significant glycemic impact, it is subtracted from total carbs to give a more accurate picture of the carbs that affect your body.
Are sugar alcohols subtracted from total carbs?
Yes, most sugar alcohols are subtracted because they have minimal glycemic impact. Erythritol is fully subtracted (0 glycemic index), while others like maltitol and xylitol are partially subtracted (about 50%). Our calculator subtracts the full amount as listed on nutrition labels. Check with your dietitian if you have specific concerns about sugar alcohols.
How many net carbs should I eat for keto?
For a standard ketogenic diet, most people aim for 20–50g of net carbs per day. The strictest approach starts at 20g, while more liberal plans allow up to 50g. The exact limit depends on your activity level, metabolism, and individual response. Our calculator shows a keto-friendly indicator when your meal total is at or below 20g.