A medium apple (about 182 grams) contains roughly 25 grams of total carbohydrates. Of those, 19 grams come from natural sugars and about 4 grams from dietary fiber. The rest is starch. That works out to around 21 net carbs once you subtract the fiber.
Carbs by Apple Size
The 25-gram figure applies to a medium apple, which is the standard reference size used by the USDA. But apples vary quite a bit in size, and so does the carb count:
- Small apple (about 150 g): ~20 g total carbs
- Medium apple (about 182 g): ~25 g total carbs
- Large apple (about 242 g): ~34 g total carbs
A half-cup of sliced apple (55 grams) has about 8 grams of carbs, which is a useful reference if you’re portioning fruit into a meal or snack.
How the Sugar Breaks Down
The 19 grams of sugar in a medium apple aren’t all the same type. Most of it is fructose, the sugar that gives fruit its sweetness. A smaller portion is glucose, and the remainder is sucrose. The exact ratio shifts depending on the variety. A Fuji apple, for example, packs about 7.7 grams of fructose per 100 grams of fruit, while a Granny Smith has only about 2.3 grams. That’s a big reason Fujis taste noticeably sweeter.
Granny Smith apples aren’t actually lower in total sugar than Fuji apples by a dramatic margin, though. The real difference in taste comes from acid content. Granny Smiths contain nearly twice as much malic acid, the compound responsible for sourness, which masks the sweetness. So a tart apple still delivers a similar amount of carbohydrate overall.
Net Carbs and Low-Carb Diets
If you’re tracking net carbs (total carbs minus fiber), a medium apple lands at about 21 grams. That’s a significant chunk of the daily 20 to 50 grams that most ketogenic diets allow, which is why apples are generally considered too high-carb for strict keto. A half apple or a small apple (around 15 to 20 net carbs) can sometimes fit into a more relaxed low-carb plan.
For other carb-conscious approaches like moderate low-carb or diabetes-friendly eating, apples are usually a reasonable choice. They pair their sugar with enough fiber to slow digestion, and their glycemic index reflects that.
Blood Sugar Impact
Despite containing 19 grams of sugar, apples have a glycemic index of just 39, which puts them firmly in the low-GI category (anything under 55 qualifies). The glycemic load, which accounts for actual portion size, is only 6 per medium apple. For context, a GL under 10 is considered low.
This means a whole apple raises blood sugar slowly and modestly compared to foods with the same amount of carbohydrate, like white bread or rice. The fiber, the water content, and the structure of the fruit itself all slow down how quickly your body absorbs the sugars. This is why whole apples behave very differently in your body than apple juice, which strips out the fiber and concentrates the sugar.
Why the Peel Matters
Eating your apple with the skin on gives you about 4 grams of fiber per medium fruit. Peel it, and you lose roughly a third of that fiber. The total carbohydrate count doesn’t change much either way since fiber is counted within the carb total, but you do lose the part that slows sugar absorption and feeds beneficial gut bacteria. If you’re eating apples specifically because they’re a lower-impact fruit, keeping the skin on is the simplest way to preserve that advantage.
Carb Differences Between Varieties
All common apple varieties fall in a similar carbohydrate range. The total sugar content between a Fuji and a Granny Smith grown under the same conditions differs by less than 15%. Where varieties diverge more noticeably is in their sugar profile. Sweeter varieties like Fuji, Royal Gala, and Golden Delicious are higher in fructose, while tart varieties like Granny Smith are lower in fructose but higher in organic acids. If you’re choosing based purely on carb count, variety matters less than size. A small Fuji has fewer total carbs than a large Granny Smith, regardless of how sweet each one tastes.