Banana Bread in Grams
A typical banana bread converts to 240 grams of all-purpose flour for 2 cups, 114 grams of butter for ½ cup, 160 grams of packed brown sugar for ¾ cup and 338 grams of mashed banana for 1½ cups, each converted with that ingredient’s own published cup weight.
A typical banana bread, converted
This page converts a typical banana bread — the standard loaf built on 2 cups of flour, half a cup of butter and a cup and a half of mashed banana — into grams, line by line. Every weight uses GramChef's ingredient-specific values, so the loaf can be mixed entirely on a scale.
Banana bread is forgiving, but it is not immune to measuring error. The banana is the biggest variable: 'about 3 bananas' can mean 280 grams of mash or nearly 400, and that swing in moisture decides whether the crumb is tender or gummy. Weighing the mash, the flour and the packed brown sugar keeps the batter's hydration where the recipe intends it.
| Ingredient | Amount | Grams |
|---|---|---|
| All-Purpose Flour | 2 cups | 240 g |
| Baking soda | 1 tsp | — |
| Salt | 1/2 tsp | — |
| Butter | 1/2 cup | 114 g |
| Brown Sugar (packed) | 3/4 cup | 160 g |
| Eggs | 2 large | — |
| Mashed Banana | 1 1/2 cups (about 3 bananas) | 338 g |
| Vanilla extract | 1 tsp | — |
Notes for this loaf
Flour and banana carry this recipe. Two cups of all-purpose flour should weigh 240 grams; a scooped cup can run 20 to 30 grams heavier, which tightens the crumb and dries the loaf. The mashed banana matters just as much — 338 grams is the target, measured after mashing, using very ripe, heavily speckled fruit. Under-ripe bananas bring less sugar and moisture, so ripeness changes the result even at the same weight.
The brown sugar figure assumes a firmly packed cup, the standard convention for this recipe, which is why 3/4 cup weighs 160 grams rather than about 120 grams loose. The butter (114 grams) should be soft enough to cream with the sugar until pale; melting it instead produces a denser, heavier loaf from exactly the same weights.
Published banana breads vary widely: flour ranges from 1 1/2 to 2 1/4 cups, banana from 1 to 2 cups, and some versions swap in oil for butter. The table above converts one typical middle version. When adapting another recipe, convert its flour and banana first — if those two weights stay in roughly the same ratio, the rest usually follows.
The weights divide cleanly for scaling. A half batch uses 120 grams of flour, 57 grams of butter, 80 grams of brown sugar and 169 grams of mashed banana. A double batch (480 grams of flour) should be baked as two loaves, not one deep one, which would set slowly and stay raw in the centre.
Frequently asked questions
How many grams of mashed banana is 1 1/2 cups?
338 grams. Mashed banana weighs about 225 grams per cup, so 1 1/2 cups comes to 338 grams. That is roughly three medium-to-large ripe bananas, but size varies enough that the scale is the reliable measure — mash first, then weigh out what is needed.
Can the butter be replaced with oil?
Yes. Swap the 114 grams of butter for 109 grams of a neutral vegetable oil — the same half-cup volume, which weighs slightly less. The loaf will be moist but a little denser, and the method changes: whisk the oil with the sugar and eggs instead of creaming it.
Why did the loaf sink or turn gummy in the middle?
The usual cause is too much banana relative to flour: well over 338 grams of mash makes a batter too wet for 240 grams of flour to set, so the centre stays damp and heavy. Weighing both removes the guesswork. Old baking soda and underbaking look similar, so check those next if the weights were right.
Can another flour be used instead of all-purpose?
Whole wheat flour weighs 113 grams per cup and absorbs more liquid, so replacing more than half of the 240 grams makes the loaf denser; a half-and-half swap keeps the crumb tender. Bread flour weighs the same per cup (120 grams) but gives a chewier, tougher crumb.