Cup (US) to Fluid ounce Conversion Calculator: Free Online Tool
Convert US cups to fluid ounces with our free online volume converter.
Cup (US) to Fluid ounce Calculator
How to Use the Calculator:
- Enter the value you want to convert in the 'From' field (Cup (US)).
- The converted value in Fluid ounce will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Volume category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Cup (US) to Fluid ounce
Converting Cup (US) to Fluid ounce involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Cup (US) = 8 fluid ouncesExample Calculation:
Convert 10 US cups: 10 × 8 = 80 fluid ounces
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
What is a Cup (US) and a Fluid ounce?
The US customary cup is a unit of volume used in the United States for cooking and serving sizes. It is defined as exactly 8 US customary fluid ounces. This equates to approximately 236.59 milliliters (mL).
The fluid ounce is a unit of volume. The US fluid ounce is defined as 1/128 of a US gallon (approx. 29.57 ml). The Imperial fluid ounce is 1/160 of an Imperial gallon (approx. 28.41 ml).
Note: The Cup (US) is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Fluid ounce belongs to the imperial/US customary system.
History of the Cup (US) and Fluid ounce
The concept of a 'cup' as a measurement unit evolved informally over centuries. The US customary cup was standardized based on the US gallon, which itself derived from the older English wine gallon. Unlike the metric cup (250 mL) or the imperial cup (approx. 284 mL), the US cup was legally defined in terms of the gallon (1 US gallon = 16 US cups).
Derived from the ounce unit of weight/mass, adapted to measure the volume of liquids like wine or water.
Common Uses for US cups and fluid ounces
Explore the typical applications for both Cup (US) (imperial/US) and Fluid ounce (imperial/US) to understand their common contexts.
Common Uses for US cups
- Cooking & Baking: The primary use is measuring liquid and dry ingredients in recipes within the United States.
- Serving Sizes: Often used to indicate serving sizes on nutritional labels in the US.
- Informal Measurement: Used informally for estimating liquid quantities.
Common Uses for fluid ounces
- Beverages: Measuring alcoholic drinks, soft drinks, and coffee servings.
- Cooking: Recipe measurements for smaller liquid ingredients.
- Medicine: Liquid medication dosages on prescription labels.
- Personal Care: Volumes of cosmetics, perfumes, and essential oils.
- Nutrition Labels: Serving sizes on food and beverage packaging.
Frequently Asked Questions
Questions About Cup (US) (cup)
How many fluid ounces are in a US cup?
There are exactly 8 US customary fluid ounces (fl oz) in 1 US cup.
How many milliliters are in a US cup?
One US cup is equivalent to approximately 236.59 milliliters (mL).
Is a US cup the same as a metric cup or an imperial cup?
No. A US cup (~236.59 mL) is smaller than both a metric cup (250 mL) used in many Commonwealth countries and an imperial cup (~284.13 mL) which is less commonly used today but part of the UK imperial system.
About Fluid ounce (fl oz)
Is a US fluid ounce the same as a UK fluid ounce?
No, the Imperial (UK) fluid ounce is slightly smaller than the US fluid ounce (approximately 28.41 ml vs 29.57 ml).
Is a fluid ounce the same as a weight ounce?
No, a fluid ounce measures volume (the space something occupies), while a weight ounce (specifically an avoirdupois ounce) measures mass (how much matter it contains). The relationship between the two depends entirely on the density of the substance being measured. For water, 1 US fluid ounce weighs approximately 1.04 avoirdupois ounces.
Conversion Table: Cup (US) to Fluid ounce
| Cup (US) (cup) | Fluid ounce (fl oz) |
|---|---|
| 1 | 8 |
| 5 | 40 |
| 10 | 80 |
| 25 | 200 |
| 50 | 400 |
| 100 | 800 |
| 500 | 4,000 |
| 1,000 | 8,000 |