Net Carbs Explained: How to Count Carbs on Keto

Every recipe on The Keto Vibe lists net carbs per serving. It’s the number most keto eaters track, and it’s easy to get wrong when you read a nutrition label. Here’s how it works, and where people slip up.

What are net carbs?

Net carbs are the carbohydrates your body digests and turns into glucose. Fiber is a carbohydrate too, but it passes through mostly undigested, so it’s subtracted:

Net carbs = total carbohydrates − fiber

That’s why an avocado, with around 8.5 g of total carbs per 100 g, counts as under 2 g net: most of its carbohydrate is fiber.

A worked example

A serving of a low-carb tortilla lists:

Label line	Amount
Total carbohydrate	12 g
Dietary fiber	9 g

Net carbs: 12 − 9 = 3 g.

US labels vs. EU and UK labels

This is where most counting mistakes happen.

• US and Canada: “Total carbohydrate” includes fiber. Subtract the fiber line to get net carbs.
• EU, UK and Australia: “Carbohydrate” already excludes fiber. That number is close to net carbs as it is. Subtracting fiber again would undercount.

Sugar alcohols: which ones count

Sugar alcohols (polyols) sweeten many “keto” products. They are partly absorbed, and some raise blood sugar more than others:

Sweetener	How to count it	Why
Erythritol	Subtract in full	Mostly absorbed and passed out in urine unchanged
Allulose	Subtract in full	A rare sugar the body barely metabolizes
Xylitol	Count about half	Partly absorbed; mild effect on blood sugar
Sorbitol	Count about half	Partly absorbed; can upset digestion
Maltitol	Count almost all	Raises blood sugar noticeably

So a bar with 20 g total carbs, 8 g fiber and 10 g erythritol has about 2 g net carbs. Swap the erythritol for maltitol and it’s closer to 10 g. Lesson 5 compares keto sweeteners in depth.

How many net carbs on keto?

A common starting point is about 20 g of net carbs a day, which is roughly where most people reach ketosis. Some people stay in ketosis at higher intakes, especially if they’re very active. Everyone is different, and if you have a medical condition, check with your doctor before changing your diet.

To set your own fat and protein targets around that carb limit, try our keto macro calculator. Once your targets are saved, every recipe on this site shows how much of your daily carb budget it uses.

Where net carbs hide

• Sauces and dressings: ketchup, barbecue sauce and sweet chili sauce are mostly sugar.
• “Low-fat” products: fat is often replaced with sugar or starch.
• Vegetables vary a lot: leafy greens, zucchini and cauliflower are very low; carrots, peas and corn add up quickly.
• Nuts: pecans and macadamias are low, cashews and pistachios are much higher.
• Milk: a cup of whole milk has around 12 g of net carbs from lactose. Cream has a fraction of that.

Curious how your instincts compare? Play Higher or Lower, or look anything up in the keto food list.

Test yourself

4 questions · +10 XP each

Question 1 of 4

A US label lists 14 g total carbohydrate and 6 g fiber. How many net carbs?

• 20 g
• 14 g
• 8 g
• 6 g