A medium banana contains about 27 grams of total carbohydrates. That’s for a banana roughly 7 to 8 inches long, weighing around 118 to 126 grams without the peel. Since bananas vary quite a bit in size, the actual carb count ranges from about 19 grams for the smallest bananas to 35 grams for extra-large ones.
Carbs by Banana Size
Banana size makes a real difference in carb count. Here’s what to expect based on USDA data:
- Extra small (shorter than 6 inches): about 19 grams of carbs
- Small (6 to 7 inches): about 23 grams of carbs
- Medium (7 to 8 inches): about 27 grams of carbs
- Large (8 to 9 inches): about 31 grams of carbs
- Extra large (9 inches or longer): about 35 grams of carbs
Most bananas sold at grocery stores fall in the medium to large range. If you’re estimating without a scale, the medium figure of 27 grams is a reasonable default.
Sugar, Starch, and Fiber Breakdown
Those 27 grams of carbs in a medium banana aren’t all sugar. About 14 grams come from sugars (a mix of sucrose, fructose, and glucose), roughly 3 grams come from dietary fiber, and the rest is starch. Sucrose actually makes up the largest share of the sugars in a ripe banana, accounting for more than 70% of the total sugar content.
The fiber content is worth noting if you track net carbs. Subtracting the 3 grams of fiber from 27 grams of total carbs gives you about 24 grams of net carbs for a medium banana. That’s the portion your body actually digests and absorbs as energy.
How Ripeness Changes the Carb Profile
The total carbs in a banana stay roughly the same whether it’s green or spotted brown. What changes dramatically is the type of carbohydrate inside.
Green bananas are high in resistant starch, a form of starch that passes through your small intestine without being digested, behaving more like fiber. As a banana ripens, enzymes convert that starch into simple sugars. By the time a banana is fully ripe (yellow with a few brown spots), it contains only about 1% starch, with total sugars climbing to around 23% of its weight. Overripe bananas have essentially no starch left at all.
This is why a green banana tastes chalky and firm while a brown-spotted one tastes noticeably sweeter. The calories and total carb grams are similar, but your body processes them differently. Green bananas cause a slower, more gradual rise in blood sugar. Ripe bananas deliver their sugar faster. If you’re managing blood sugar levels, this distinction matters more than the total carb number on its own.
Bananas Compared to Other Fruits
Bananas sit on the higher end of the carb spectrum for fruit. A medium apple has about 25 grams of carbs, making it comparable. A cup of strawberries, by contrast, has only about 12 grams. A medium orange falls around 15 grams. Grapes pack roughly 27 grams per cup, similar to a banana.
The difference is density. Bananas have less water content than most other popular fruits, which concentrates their carbohydrates into a smaller, more portable package. That’s part of what makes them a go-to snack for athletes, but it also means they add up faster if you’re watching carb intake on a keto or low-carb diet, where a single medium banana could use up a significant chunk of a daily carb allowance.
Practical Tips for Tracking
If you’re logging carbs precisely, weigh the edible portion (without the peel) on a kitchen scale. Banana peels account for roughly 30 to 40% of the total weight, so a banana that weighs 180 grams whole might only have 110 grams of edible fruit. Use 23 grams of carbs per 100 grams of banana flesh as a quick conversion.
Slicing a banana in half is a simple way to cut the carb load while still getting the flavor and potassium. Half a medium banana adds about 13 to 14 grams of carbs to a smoothie or bowl of oatmeal, which fits more comfortably into most carb-conscious meal plans.