When you’re on a ketogenic diet, every gram of carbohydrate you eat counts. Having said this, those who are eating high-fiber carbs (primarily in the form of vegetables) may be able to use "net carbs" when counting their carbs from these whole food sources. Net carbs are the amount of carbohydrates a food contains after subtracting the fiber. Fiber-based carbs are not well digested by your digestive system and therefore have little, if any, effect on your blood sugar. As a result, some people choose to not count these carbs against their carb allowance on any given day. You can either choose to subtract the carbs from fiber (whole food sources only) to get the ‘net carbs,’ or simply count total carbs. For most, it will not be a substantial difference.
Here is an example for a serving of Broccoli: 6.6g total carbs - 2.6g of fiber = 4g net carbs
In some cases, specifically with avocado, this makes a big difference: Avocado: 11.8g total carbs - 9.2g of fiber = 2.5g net carbs. So, we encourage you to eat avocados often because of their high-fat content and low net carb count.