Net Carbs Calculator
Calculate net carbs by subtracting fiber and (optionally) sugar alcohols from total carbohydrates. Net carbs are the carbs that actually impact blood sugar — essential for keto and low-carb diet tracking.
Formula & Reference
| Variable | Symbol | Formula | Units |
|---|---|---|---|
| Net Carbs Calculator | — | Net Carbs = Total Carbs - Fiber - Sugar Alcohols (÷2) | grams |
Step-by-Step Examples
Total carbs=25g, fiber=8g, sugar alcohols=6g.
- Net = 25 - 8 - (6/2) = 25 - 8 - 3 = 14g
- Sugar alcohols only count half toward net carbs
- Still significant for strict keto (target <20-25g/day total)
Broccoli: total carbs=6g, fiber=2.4g, no sugar alcohols.
- Net = 6 - 2.4 - 0 = 3.6g
- Very low net carb food, ideal for keto
Total carbs=20g, fiber=3g, no sugar alcohols.
- Net = 20 - 3 - 0 = 17g
- High net carbs relative to keto daily limit
Real-World Applications
Common Mistakes to Avoid
Most sugar alcohols (erythritol, xylitol) are only partially absorbed. The half-count rule is standard, though erythritol is sometimes counted at zero.
Some companies undercount net carbs on labels. Always verify by checking total carbs, fiber, and sugar alcohols on the nutrition facts panel yourself.
Soluble fiber slows digestion more than insoluble fiber, but standard net carb math subtracts all fiber types equally — a simplification, not a perfect science.