180 g6.35 oz
A medium banana, 7 to 8 in (18 to 20 cm) long, weighs about 180 g (6.3 oz) with its peel. Peeled, it weighs about 118 g (4.2 oz), the USDA’s figure, because the peel makes up 35 to 40% of the fruit’s weight. An extra-large banana gives about 152 g of fruit, a small one about 101 g.
| Largest bunch on record473 bananas, Canary Islands, 2001 | 130 kg287 lb |
|---|---|
| Medium banana, with peelAbout 118 g of fruit plus the peel | 180 g6.35 oz |
| Extra large, peeled9 in (23 cm) or longer | 152 g5.36 oz |
| Medium, peeled7 to 7⅞ in (18 to 20 cm) long | 118 g4.16 oz |
| Small, peeled6 to 6⅞ in (15 to 17.5 cm) long | 101 g3.56 oz |
| Extra small, peeledUnder 6 in (15 cm) | 81 g2.86 oz |
USDA FoodData Central sorts bananas by length and gives the weight of the peeled fruit. A medium banana, 7 to 7⅞ in long, gives 118 g (4.2 oz). A large one of 8 to 8⅞ in gives 136 g, an extra large one of 9 in or more 152 g, a small one 101 g and an extra small one under 6 in just 81 g.
The peel adds a lot. A 2024 study in the journal Plants puts it at 35 to 40% of a banana’s total weight, so a medium banana with its 118 g of fruit weighs roughly 180 to 200 g before peeling, by our maths. About 75% of the peeled fruit is water.
Very slightly. Bananas are rich in potassium, and a small fraction of all potassium is the radioactive isotope potassium-40: about 0.0117% of natural potassium. At 358 mg of potassium per 100 g, according to USDA data, a medium banana holds about 420 mg.
The dose is tiny. The US Environmental Protection Agency says eating one banana gives a dose of about 0.1 microsieverts (0.01 millirem), and you would need to eat about 100 bananas to match the radiation everyone in the United States gets each day from natural sources. The body also keeps its potassium level steady and gets rid of the excess, so the dose from bananas does not build up.
Guinness World Records lists the largest bunch of bananas as one of 473 bananas weighing 130 kg (286 lb 9 oz). It was grown by Kabana SA and Tecorone SL on El Hierro in the Canary Islands, Spain, and recorded on 11 July 2001. That works out to about 275 g per banana on average, well above an ordinary medium banana.
A medium banana weighs about 180 g with its peel and about 118 g peeled. A large peeled banana weighs about 136 g and a small one about 101 g.
About 118 g (4.2 oz) for a medium banana, according to USDA FoodData Central. The peel is 35 to 40% of the whole fruit’s weight.
About two and a half medium bananas with their peels on, at roughly 180 g each. Peeled, a pound (454 g) is about four medium bananas.
Barely. The EPA puts the dose from eating one banana at about 0.1 microsieverts and says it would take about 100 bananas to equal one day of natural background radiation in the US.
Last checked October 4, 2026.
