Bananas are a staple fruit in smoothies, baking, and meal prep, and the calorie count changes significantly depending on how you measure them. A standard cup of sliced banana delivers about 134 calories, while a cup of mashed banana contains roughly 200 calories, because mashing removes air pockets and packs more fruit into the same cup. This tool converts cup volume into grams using standard density values and then calculates calories and macros from USDA nutrition data.
You can choose between sliced and mashed banana, or enter a custom grams-per-cup value if your recipe calls for a different packing density. The calculator also shows carbohydrate, protein, fiber, and sugar totals, plus a simple two-step breakdown of every result.
Meal planners, smoothie fans, fitness enthusiasts, and anyone tracking calories will find this useful for estimating portions quickly without weighing the fruit every time.
🍌 Banana Calories Per Cup Calculator
Estimate calories and macros for mashed or sliced banana by cup.
Quick Start
Using the calculator takes just a few seconds. Start by typing the number of cups your recipe calls for — you can use decimals such as 0.5 or 1.25. Next, choose the banana form that matches how the fruit is prepared in your recipe: sliced banana is loose and contains more air pockets, while mashed banana is dense and packs more fruit into the same cup. If your meal plan is based on a food-scale weight instead of a standard cup, tick the custom grams option and enter your own grams-per-cup value to get a more precise estimate that reflects your packing method.
- Type the number of cups (for example, 1 or 0.75).
- Select sliced banana, mashed banana, or enable the custom grams field.
- Press Calculate to see the total calories plus carbohydrate, protein, fiber, and sugar.
- Use Reset to clear the inputs and start a new estimate.
How It Works
The calculator uses a simple two-step method. First it converts your cup volume into grams by multiplying the number of cups by a standard grams-per-cup density: 150 g for sliced banana and 225 g for mashed banana. Then it applies the nutrient content of raw banana per 100 g, taken from the USDA FoodData Central entry: 89 kcal, 22.84 g carbohydrate, 1.09 g protein, 2.6 g fiber, and 12.23 g sugar.
Calories = cups × grams per cup × (89 kcal ÷ 100). For example, 1 cup of sliced banana is 1 × 150 × 0.89 = 134 kcal. The same cup filled with mashed banana is 1 × 225 × 0.89 = 200 kcal. Every macro in the results follows the same pattern using the corresponding nutrient value per 100 g, so the breakdown always matches the calorie math.
Because the density of banana depends on how it is cut and packed, the calculator relies on widely referenced cup weights from the USDA food-portion database. These are the same values used by popular nutrition tracking apps, which keeps your estimates consistent with other tools you might already use.
Worked Examples
Example 1 — one cup sliced: 1 cup × 150 g/cup = 150 g. Calories = 150 × 89 ÷ 100 = 133.5 kcal, which rounds to 134 kcal. Carbs = 150 × 22.84 ÷ 100 = 34.3 g.
Example 2 — half cup mashed: 0.5 cup × 225 g/cup = 112.5 g. Calories = 112.5 × 89 ÷ 100 = 100 kcal. Fiber = 112.5 × 2.6 ÷ 100 = 2.9 g.
Example 3 — 1.5 cups sliced for a smoothie: 1.5 × 150 = 225 g. Calories = 225 × 89 ÷ 100 = 200 kcal. Sugar = 225 × 12.23 ÷ 100 = 27.5 g.
Example 4 — custom density for firmly packed mash: if your food scale shows that 180 g fills one cup, enter 180 in the custom grams field. One cup then gives 180 g and 160 kcal, which is a more honest estimate for your packing style.
Reference Table
The table below summarizes the nutrient totals for the most common cup amounts using the standard densities. Values are rounded to one decimal place.
| Banana form | Grams per cup | Calories | Carbs | Fiber | Protein |
|---|---|---|---|---|---|
| Sliced | 150 g | 134 kcal | 34.3 g | 3.9 g | 1.6 g |
| Mashed | 225 g | 200 kcal | 51.4 g | 5.9 g | 2.5 g |
| Sliced (½ cup) | 75 g | 67 kcal | 17.1 g | 2.0 g | 0.8 g |
| Mashed (½ cup) | 112.5 g | 100 kcal | 25.7 g | 2.9 g | 1.2 g |
For the complete raw banana nutrient profile, including vitamins and minerals, see the USDA FoodData Central entry for raw bananas at fdc.nal.usda.gov.
Tips & Best Practices
- Use a real measuring cup and level the banana with a spatula rather than pressing it down; the standard cup weights assume a loosely filled cup.
- For baking, professional recipes usually list mashed banana by weight because ripeness changes moisture and density. If you have a scale, weigh the fruit and use the custom grams field with the weight that fills your cup.
- For smoothies, frozen slices weigh about the same as fresh, so the calorie estimate stays close — but frozen fruit is typically added by weight or piece count rather than by cup volume.
- Ripeness matters. A very ripe banana has slightly more sugar and calories per 100 g than a greener one. The USDA values used here represent a raw, typical banana at normal eating ripeness.
- Keep a mental sanity check: a medium banana (around 118 g of peeled flesh) has roughly 105 kcal, 27 g of carbs, and 3 g of fiber, so your cup-based estimate should land in a similar range.
Frequently Asked Questions
Why is mashed banana higher in calories per cup? Mashing removes trapped air and lets you fit more banana into the same volume, so each cup contains more grams — 225 g versus 150 g for sliced — and therefore more calories and macros.
Are the results exact? Nutrient values vary by ripeness, variety, and growing conditions, and cup density varies with how you fill the cup. Treat the output as a solid estimate for meal planning rather than a lab measurement.
Does the peel count toward the calories? No. The USDA values and this calculator refer to the edible peeled flesh only. A medium banana with its peel weighs about 150 g, but the peeled fruit is closer to 118 g.
Can I use this for banana bread? Yes — mashed banana is the standard form for banana bread. Most loaves call for 1 to 2 cups, which means roughly 200 to 400 kcal from banana alone before you add flour, sugar, and fat.
Where does the 150 g per cup figure come from? It comes from standard portion-weight references used in nutrition databases, originally measured by weighing many samples of loosely packed sliced fruit. The same value appears in the USDA database and in major calorie tracking apps.