Tool 14/54·Calculators
Subtract fiber and sugar alcohols from total carbs to find the carbs that actually count.
Found on the “Total Carbohydrate” line of the Nutrition Facts panel.
Listed under Total Carbohydrate. Leave blank if not present.
Only enter if “Sugar Alcohols” appears on the label. Select the type for accurate absorption.
Add each food item to keep a running total for the day.
Daily Net Carb Target (g)
Calculate a food above, then tap “Add” to track it here.
Readout
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Enter total carbs to start
Add fiber and sugar alcohols to see the full breakdown in real time.
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Net carbs represent the carbohydrates that are actually digested and absorbed into your bloodstream. When you eat high-fiber vegetables or products sweetened with erythritol, the listed carb count on the label is misleading — your body does not process all of those carbs. The formula is simple: Net Carbs = Total Carbs − Fiber − (Sugar Alcohols × non-absorbed fraction).
Why Fiber Counts as Zero
Humans lack the digestive enzymes to break down dietary fiber into glucose. Soluble fiber is fermented by gut bacteria into short-chain fatty acids, and insoluble fiber passes through entirely. Neither raises blood sugar in a meaningful way, so fiber is fully excluded from net carb calculations.
This is where most people go wrong. Many keto-friendly products advertise “0 net carbs” while using maltitol — a sugar alcohol that is 90% absorbed, nearly as impactful as table sugar. Erythritol, on the other hand, is excreted almost entirely via urine and has virtually no effect on blood glucose or insulin. When buying low-carb products, always check the ingredient list for the specific sugar alcohol used, not just the net carb claim on the front of the package.
| Sugar Alcohol | % Absorbed | Net carbs per 10g |
|---|---|---|
| Erythritol | 0% | 0g |
| Xylitol | 50% | 5g |
| Sorbitol | 50% | 5g |
| Maltitol | 90% | 9g |
| Isomalt | 50% | 5g |
| Lactitol | 40% | 4g |
Most people following a ketogenic diet target 20–50g net carbs per day to stay in ketosis. Counting net carbs instead of total carbs allows you to eat generous portions of leafy greens, broccoli, cauliflower, and other fiber-rich vegetables without hitting your limit. A cup of raw broccoli has about 6g total carbs but only 4g net carbs — and vegetables like spinach can be eaten almost freely. Tracking with an app like Caloria makes this effortless because net carbs are calculated automatically from the label data.
01
Net carbs are the carbohydrates that your body actually digests and converts to glucose. They are calculated by subtracting dietary fiber and the non-absorbed portion of sugar alcohols from total carbohydrates. Fiber passes through your digestive system largely unabsorbed, so it has minimal impact on blood sugar. Net carbs are the number that matters most for low-carb and ketogenic diets.
02
Sugar alcohols vary widely in how much the body absorbs. Erythritol is mostly excreted unchanged (0% effective carb impact), while maltitol is about 90% absorbed — nearly as much as regular sugar. Xylitol and sorbitol fall in the middle at roughly 50%. Always check the specific sugar alcohol on a label rather than assuming all are equal, since using maltitol-heavy "sugar-free" products can stall ketosis.
03
Find the "Total Carbohydrate" line on the Nutrition Facts panel. Subtract the grams of Dietary Fiber listed beneath it. If sugar alcohols are listed, identify which type and subtract based on its absorption factor (e.g., subtract 100% of erythritol, 50% of xylitol, only 10% of maltitol). In the US, labels typically list net carbs as "Total Carbs minus Fiber minus Sugar Alcohols," but this oversimplifies maltitol, so reading the ingredient list matters.
04
Most ketogenic diet practitioners track net carbs and aim for 20–50 g per day. Counting total carbs is more conservative and is sometimes recommended for people with type 2 diabetes or those who find net carb counting stalls their progress. Tracking net carbs gives more dietary flexibility and allows high-fiber vegetables like broccoli and spinach to fit easily into a keto plan.
05
Soluble fiber is fermented by gut bacteria and produces short-chain fatty acids rather than glucose, so it has minimal direct blood sugar impact. Insoluble fiber is not digested at all. For most people with normal digestion, the glycemic effect of fiber is negligible, which is why it is excluded from net carb counts. However, people with very sensitive blood sugar regulation may want to monitor their individual response.
06
Yes, completely free with no sign-up required. Use it as many times as you like — enter different foods, switch sugar alcohol types, and use the daily tracker to keep a running total throughout the day. For ongoing logging and macro tracking, the Caloria app syncs everything automatically.