How many carbs are in a banana?

One medium banana has 27g of carbs (24g net). Comparison by size, ripeness, and how it affects blood sugar.

Written by

Carb Lens Editorial

Nutrition writers & product team

Medically reviewed by

Dr. Alicia Nguyen, RD, CDCES

Registered Dietitian · Certified Diabetes Care & Education Specialist · 12+ years clinical experience

Published May 27, 2026 3 min readEditorial policy

A medium banana (about 118g, 7-8 inches long) has 27g of carbs, 14g of which is sugar, with 3g of fiber — net carbs land around 24g.

By size

Size	Weight	Carbs
Extra small (<6")	81g	19g
Small (6-7")	101g	23g
Medium (7-8")	118g	27g
Large (8-9")	136g	31g
Extra large (>9")	152g	35g

Ripeness matters more than people think

As a banana ripens, starch converts to sugar:

**Green banana**: ~80% starch, lower glycemic index (~30)
**Yellow banana**: balanced, GI around 50
**Spotty / brown banana**: mostly sugar, GI around 60

The *total* carbs barely change with ripeness — but the speed they hit your blood does.

Blood sugar impact

A medium ripe banana raises glucose 30-50 mg/dL in most people, peaking around 45 minutes. Pairing with peanut butter or Greek yogurt blunts the spike significantly.

Comparison to other fruit (per serving)

Apple (medium): 25g
Orange (medium): 15g
Strawberries (1 cup): 12g
Grapes (1 cup): 16g

About the author

Carb Lens Editorial — Nutrition writers & product team. The Carb Lens editorial team writes practical, source-checked guides on carbs, blood sugar, and everyday nutrition. Every article is drafted by our writers and cross-referenced against USDA FoodData Central and peer-reviewed clinical guidelines.

How we source and review this article

Nutrition figures come from the USDA FoodData Central database. Blood-sugar and glycemic-load framing follows guidance from the American Diabetes Association and World Health Organization healthy-diet recommendations. Every article is medically reviewed by Dr. Alicia Nguyen, RD, CDCES before publishing and re-checked on a rolling basis. See our full editorial & medical review policy.

This article is for general information and is not a substitute for medical advice. If you're managing diabetes or another condition, always defer to your care team.