Free macro tool
Net Carbs Calculator
Enter the total carbohydrate, fiber and sugar alcohols from a food label and choose how much of the sugar alcohols to subtract. The answer is net carbs, in grams.
Worked example
A food with 30 g of total carbohydrate, 8 g of fiber and 10 g of sugar alcohols has 17 g of net carbs when half of the sugar alcohols are subtracted.
Calculate net carbs
The result below starts from the example's numbers. Change any field and it updates as you type.
Track this target every day
Use the number above as your daily goal in CalorTracker, then log meals by photo, voice or text and see where your day stands against it. Free to start, no card needed to explore.
Results are estimates from published formulas, not medical advice. Your own body can sit above or below them.
Where the formulas come from, and how we check them: how we calculate.
The net carbs formula
Net carbs = total carbohydrate − dietary fiber − a share of the sugar alcohols. On a US label, total carbohydrate includes the fiber, the sugars and any sugar alcohols (21 CFR 101.9), which is why they can be taken back out. The label itself does not give a net carbs figure.
Why the sugar alcohol part is a choice
"Net carbs" is not a defined term on a US Nutrition Facts label, so there is no official rule for it. Everyone subtracts fiber. For sugar alcohols, people subtract all, half or none, because different sugar alcohols are absorbed to different degrees and the label does not say which is which. The calculator lets you pick: all, half (the default) or none, and shows the arithmetic so you can see what you chose.
- All: total − fiber − sugar alcohols.
- Half: total − fiber − half the sugar alcohols.
- None: total − fiber.
Using it with a net carb limit
If you keep to a daily net carb limit, add up the net carbs of what you eat against it. The keto calculator sets calories, protein and fat around a limit of 20, 30, 50 g. This page makes no health claims about eating fewer net carbs; talk to your doctor or a registered dietitian before changing how you eat if you have a medical condition or take medication.
Calories still count whatever the net carbs are. A food does not become free because its net carbs are low.