Start with total carbohydrate. Then look at fiber separately, so you can see exactly what is being counted.
What the food pages show
Our starter database uses US-style USDA reference values per 100 g of edible food. Total carbohydrate includes fiber. The separate “Carbs − fiber” number is simply total carbohydrate minus dietary fiber; it makes no adjustment for sugar alcohols.
For example, the avocado entry lists 8.53 g total carbohydrate and 6.70 g fiber per 100 g. Subtracting gives 1.83 g. The site displays rounded results, while the calculator uses the stored values.
What “net carbs” means here
Because different products and calculators can use different deductions, we label our number “Carbs − fiber” and show the arithmetic. It is a calculation, not a personalized daily target.
Adding your own label
The manual entry form expects US-style total carbohydrate including fiber, per 100 g. Do not enter a carbohydrate value that already excludes fiber and then subtract that fiber again. Leave optional unknown nutrients blank; a blank never means zero.
Follow the source
Each food page lists its full reference description, FoodData Central identifier and the source page we viewed. Read our methodology and the FDA guide to the Nutrition Facts label.