US Cup to US Fluid Ounce Converter

One US Cup equals 8 US Fluid Ounce (1 cup = 8 fl-oz). Multiply a US Cup value by 8 to get the equivalent in US Fluid Ounce. Use the calculator above for instant results, or follow the formula, worked examples, and reference table below.

Formula

fl-oz = cup × 8

Multiply the US Cup value by 8 to get the equivalent value in US Fluid Ounce.

Example Conversions

1 US Cup (cup)

8 US Fluid Ounce (fl-oz)

5 US Cup (cup)

40 US Fluid Ounce (fl-oz)

10 US Cup (cup)

80 US Fluid Ounce (fl-oz)

25 US Cup (cup)

200 US Fluid Ounce (fl-oz)

100 US Cup (cup)

800 US Fluid Ounce (fl-oz)

Conversion Table

Common conversion values from US Cup to US Fluid Ounce
US Cup (cup) US Fluid Ounce (fl-oz)
0.1 0.8
0.5 4
1 8
2 16
5 40
10 80
25 200
50 400
100 800
250 2000
500 4000
1000 8000

How to Convert Manually

Use these steps to convert US Cup values to US Fluid Ounce without the calculator.

  1. Write down the value in US Cup (cup) that you want to convert.
  2. Multiply that value by 8.
  3. For example, 10 US Cup × 8 = 80 US Fluid Ounce.
  4. Label the result as US Fluid Ounce (fl-oz).

Relative Size Comparison

1 US Cup
1cup
1 US Fluid Ounce0.125US Cups

This chart shows the visual difference in size between exactly one US Cup and one US Fluid Ounce.

About US Cup and US Fluid Ounce

The US cup is 8 US fluid ounces, about 236.6 milliliters. It is the backbone of American recipe measurement for both liquids and dry ingredients. The US fluid ounce is about 29.574 milliliters, one eighth of a US cup. Beverage cans, cosmetics, and baby formula in the US are labeled in fluid ounces. One US Cup equals 8 US Fluid Ounce (1 cup = 8 fl-oz). US Cup to US Fluid Ounce conversion comes up most often in American recipe measurements and in coffee maker capacities, typically when figures need restating for US beverage can and bottle sizes.

Precision and Rounding: US and imperial volume units share names but differ in size (an imperial gallon is about 20% larger than a US gallon), so confirm which system a figure uses before converting. Kitchen work tolerates rounding to the nearest milliliter or quarter-teaspoon; fuel, chemistry, and brewing need three or more decimal places.

Conversion factors per NIST Special Publication 811 and the BIPM SI Brochure (9th edition) (reference).

Worked Example

15 US Cup equals 120 US Fluid Ounce.

15 cup × 8 = 120 fl-oz

FAQ

How do I convert US Cup to US Fluid Ounce?

Multiply the US Cup value by 8 to get the equivalent value in US Fluid Ounce.

What is the formula for US Cup to US Fluid Ounce?

The formula is fl-oz = cup × 8.

How many US Fluid Ounce are in 1 US Cup?

1 US Cup equals 8 US Fluid Ounce.

Can I convert US Fluid Ounce back to US Cup?

Yes. 1 US Fluid Ounce equals 0.125 US Cup, and the related converter can reverse the calculation.

What are common names for US Cup and US Fluid Ounce?

US Cup is shown as cup and may also be searched as cups, us cups. US Fluid Ounce is shown as fl-oz and may also be searched as fluid ounces, fl oz, us fl oz.

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