# How do I convert cups to pounds?

Converts cups to pounds and back for water, milk, flour, sugar, and other ingredients, from what each one weighs per cup.

- Page: https://www.acalculator.org/convert/cups-to-lbs
- JSON spec: https://www.acalculator.org/convert/cups-to-lbs.json
- Version: 07c31a2a6bf4

## Default answer

Example with the default inputs (Cups (cup) 1, Ingredient All-purpose flour, 125 g per cup): 1 cup = 0.275578 lb (All-purpose flour, 125 g per cup).

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| value | Cups (cup) | The amount in cups to convert. |
| result | Pounds (lb) | The same amount in pounds. |
| ingredient | Ingredient | What you are measuring. A cup of flour weighs less than a cup of water. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| value | Cups (cup) | The amount in cups to convert. |
| result | Pounds (lb) | The amount in pounds. |

## Method

lbs = cups × 125 ÷ 453.59237, where grams per cup depends on the ingredient (all-purpose flour: 125 g)

## Assumptions

- Grams per cup are USDA FoodData Central (SR Legacy) portion weights for one level US cup (8 US fluid ounces): all-purpose flour 125 g (FDC 168894), granulated sugar 200 g (FDC 169655), brown sugar, packed 220 g (FDC 168833), powdered sugar, unsifted 120 g (FDC 169656), whole milk 244 g (FDC 171265), butter 227 g (FDC 173410), olive oil 216 g (FDC 171413), honey 339 g (FDC 169640), white rice, uncooked 185 g (FDC 169756).
- Water is pure water: 0.999975 kg per liter at 4 °C and 0.998207 kg per liter at 20 °C, from the Tanaka et al. (2001) density formula.
- How you fill the cup changes the weight: packed, sifted, or scooped flour can differ by 20% or more.
- The answer shows at most 6 decimal places; the calculation keeps full precision.

## Worked examples

1. value = 1, ingredient = flour gives result = 0.275578. Source: USDA FoodData Central SR Legacy 168894: 1 cup = 125 g.
2. value = 4, ingredient = sugar gives result = 1.763698. Source: USDA FoodData Central SR Legacy 169655: 1 cup = 200 g.

## FAQ

### How many pounds are in a cup?

It depends on the ingredient, because a volume does not fix the weight. 1 cup is about, in pounds: all-purpose flour 0.2756; granulated sugar 0.4409; brown sugar, packed 0.485; powdered sugar, unsifted 0.2646; water at 4 °C 0.5216; water at 20 °C 0.5207; whole milk 0.5379; butter 0.5004; olive oil 0.4762; honey 0.7474; white rice, uncooked 0.4079.

### How do I convert cups to lbs?

lbs = cups × 125 ÷ 453.59237, where grams per cup depends on the ingredient (all-purpose flour: 125 g). For example, 1 cup of all-purpose flour is 0.275578 lbs.

### Why does my cup of flour weigh a different amount?

Flour packs down. Spooned and levelled flour weighs about 125 g a cup, but a scooped or packed cup can weigh 20% more. For baking, weighing is more accurate than measuring by volume.

## Sources

- USDA FoodData Central, SR Legacy portion weights for 1 cup: FDC 168894 all-purpose flour 125 g; FDC 169655 granulated sugar 200 g; FDC 168833 brown sugar, packed 220 g; FDC 169656 powdered sugar, unsifted 120 g; FDC 171265 whole milk 244 g; FDC 173410 butter 227 g; FDC 171413 olive oil 216 g; FDC 169640 honey 339 g; FDC 169756 white rice, uncooked 185 g. https://fdc.nal.usda.gov/
- Tanaka, M. et al. (2001), Recommended table for the density of water between 0 °C and 40 °C based on recent experimental reports, Metrologia 38, 301–309: pure water 999.9749 kg/m³ at 4 °C and 998.2067 kg/m³ at 20 °C. https://doi.org/10.1088/0026-1394/38/4/3
- NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B.8. https://www.nist.gov/pml/special-publication-811