Net Carbs Calculator

How to use

1. 1Pick a methodology: US (FDA) standard for the common keto default, Atkins for half-subtraction of non-erythritol polyols, or EU label when the carbohydrate value already excludes fiber.
2. 2Copy total carbohydrates from the Nutrition Facts panel into the Total carbs field. The value is per serving.
3. 3Enter grams of fiber, erythritol, allulose, and any other sugar alcohols listed on the label. Leave a field at zero if it is not listed.
4. 4Set Servings eaten to scale the result. Use 0.5 for half a serving or 2 for two servings.
5. 5Read net carbs per serving and the scaled total. Use the breakdown table to see exactly which component was subtracted.
6. 6Tap Copy summary to paste a clean text breakdown into a food log, spreadsheet, or message.

About this tool

Net Carbs Calculator turns the Nutrition Facts panel on any package into the net (digestible) carbohydrate figure people actually track on keto, low-carb, and diabetes-aware diets. Type the per-serving values straight from the label: total carbohydrates, dietary fiber, erythritol, allulose, and any other sugar alcohols (maltitol, sorbitol, xylitol, isomalt, lactitol, mannitol, hydrogenated starch hydrolysates). The tool subtracts each component using the convention you pick at the top of the page. US (FDA) standard subtracts fiber, erythritol, allulose, and all other sugar alcohols in full, which is the most common keto default. Atkins subtracts fiber, erythritol, and allulose in full but only half of the non-erythritol polyols because they raise blood glucose partially, matching the original Atkins planning convention. EU label mode recognizes that European nutrition labels already exclude fiber from the carbohydrate value, so it does not subtract fiber a second time. A serving multiplier lets you size the result for half a bar, two scoops of ice cream, or a whole bag in one number. The result panel shows net carbs per serving in large type, the total for the chosen number of servings, and a percentage so you can see what share of the total carbs were subtracted. A subtraction breakdown table reveals exactly which component contributed which grams, useful for sanity-checking unfamiliar products. A reference table covers the published glycemic index of common polyols so you can decide whether the Atkins or US standard view is more appropriate for a given ingredient. Useful for clean keto bars and ice creams, sugar-free chocolate with maltitol, allulose-sweetened products, low-carb baking, comparing two competing brands, and tightening daily carb totals against a target. All math runs locally in your browser; the labels you enter are never uploaded. This tool is for nutrition planning and label comparison, not medical advice.

Free to use. Works in your browser. No signup, no login.