Banana

One US cup of banana weighs 225 grams. Going the other way, 100 grams is about 0.44 cups.

Also called mashed banana, ripe banana, banana pulp.

Sources agree within 0.9%, well inside the 5% tolerance for the liquid category. USDA FDC 173944 (Bananas, raw) publishes 1 cup mashed at 225 g (0.951 g/ml). King Arthur's Ingredient Weight Chart lists mashed bananas at 227 g per cup (0.9595 g/ml).

The King Arthur figure is exactly 8 fluid ounces at 28.35 grams per fluid ounce, which is the fluid-ounce mass equivalent rather than a bench density measurement, the same convention documented on the milk, yogurt, heavy cream and coconut milk entries. For those dairy entries, the resulting figure was below water density and therefore physically impossible, so King Arthur's number was rejected. For mashed banana the same conversion happens to land within 1 percent of USDA's bench measurement, because mashed banana pulp is coincidentally close to the density of water.

This is treated as a fortunate agreement rather than as a corroborated measurement, and the King Arthur figure is included without a rejection flag. Bananas are roughly 75 percent water carrying starch, sugars, dietary fiber and small amounts of protein and fat. As green bananas ripen, starch converts to simple sugars (sucrose, glucose, fructose) but the total dry matter stays similar, so density does not shift meaningfully across ripeness stages that a home cook would use.

Overripe bananas do lose some water through transpiration and can weigh slightly less per fresh banana, but the mashed density per unit volume remains close to USDA's 225 g per cup figure. The comparison between USDA's mashed cup at 225 g and USDA's sliced cup at 150 g is instructive: same fruit, same cup volume, 50 percent more banana by weight when mashed. The difference is entirely air.

Sliced banana rounds pack loosely with substantial air pockets between rounds; mashing collapses those pockets. Recipes that call for cups of banana without specifying mashed or sliced will produce different results by weight, and this is why banana bread recipes almost universally specify mashed, since a consistent volume of mashed banana is a consistent weight of banana. The yields section provides USDA's own piece weights for small, medium, large and extra-large peeled bananas, which are more useful than cup measurements for recipes that call for a number of bananas (as most banana bread recipes do).

USDA defines these size categories by length: small under 6 inches (101 g), medium 7 to 7-7/8 inches (118 g), large 8 to 8-7/8 inches (136 g), extra-large 9 inches and up (152 g). These figures are for edible pulp after peeling and are the standard reference across nutrition databases. Retail bananas in North American supermarkets typically fall in the medium to large range.

Cavendish is the dominant commercial cultivar and is what USDA's figures describe; other cultivars such as Gros Michel, plantains, red bananas and burro bananas have different sizes, densities and starch content, and are covered by separate USDA records where they exist. Two sources agreeing within category tolerance, so this entry publishes USDA's bench figure and is held at medium confidence until an independent third is found.