# What is 8 oz butter to cups?

Converts ounces of butter to cups and back, from the weight of 1 cup (butter: 227 g).

- Page: https://www.acalculator.org/convert/8-oz-butter-to-cups
- JSON spec: https://www.acalculator.org/convert/8-oz-butter-to-cups.json
- Version: a8be03b7cf01

## Default answer

Example with the default inputs (Ounces (oz) 8, Ingredient Butter, 227 g per cup): 8 oz = 0.999102 cups (Butter, 227 g per cup).

## Inputs

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

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| value | Ounces (oz) | The amount in ounces to convert. |
| result | Cups (cup) | The amount in cups. |

## Method

cups = oz × 28.349523125 ÷ 227, where grams per cup depends on the ingredient (butter: 227 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).
- Ounces here are avoirdupois ounces, a weight: 1 oz = 1/16 lb = 28.349523125 g. A US fluid ounce is a volume.
- 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.
- Exact on the typed decimals: at most 6 decimal places (6 significant digits below 0.0001), rounded half up; an answer of 1 billion or more shows at most 15 significant digits.

## Worked examples

1. value = 8, ingredient = butter gives result = 0.999102. Source: USDA FoodData Central SR Legacy 173410: 1 cup = 227 g.
2. value = 16, ingredient = sugar gives result = 2.267962. Source: USDA FoodData Central SR Legacy 169655: 1 cup = 200 g.

## FAQ

### What is 8 oz of butter in cups?

8 oz of butter is 0.999102 cups. The formula is cups = oz × 28.349523125 ÷ 227: USDA FoodData Central lists 1 level US cup at 227 g (butter, FDC 173410).

### How do I convert ounces of butter to cups?

cups = oz × 28.349523125 ÷ 227, where grams per cup depends on the ingredient (butter: 227 g). For example, 16 oz of butter is 1.998204 cups.

### How many sticks of butter are in a cup?

2. USDA FoodData Central lists 1 stick of salted butter at 113 g and 1 cup at 227 g. So 8 oz of butter (226.796185 g) is 0.999102 cups, about 2 sticks.

### How many cups is 8 oz of another ingredient?

It depends on the ingredient, because a weight does not fix the volume. 8 oz is about, in cups: all-purpose flour 1.814; granulated sugar 1.134; brown sugar, packed 1.031; powdered sugar, unsifted 1.89; water at 4 °C 0.9586; water at 20 °C 0.9603; whole milk 0.9295; olive oil 1.05; honey 0.669; white rice, uncooked 1.226. Pick the ingredient in the converter for its exact answer.

### Is an ounce here a weight or a volume?

A weight: the avoirdupois ounce, 1/16 of a pound (28.349523125 g exactly). A US fluid ounce (29.57 mL) measures volume, as on the oz to cups page.

## Sources

- USDA FoodData Central, SR Legacy 173410, Butter, salted: portions 1 cup = 227 g, 1 stick = 113 g, retrieved 2026-10-19. https://fdc.nal.usda.gov/food-details/173410/nutrients
- 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: Factors for Units Listed Alphabetically (bold factors are exact), retrieved 2026-10-18. https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors/nist-guide-si-appendix-b8
- NIST SP 811 (2008), footnotes to Appendix B: 1 lb = 0.45359237 kg exactly (footnote 22); 1 lbf = 4.4482216152605 N exactly with standard gravity, 9.80665 m/s² (footnote 23), retrieved 2026-10-18. https://www.nist.gov/pml/special-publication-811/nist-guide-si-footnotes