Cup (US) to Fluid Ounce (US) Converter

Volume Converter

40 units available

Decimals:

From

To

8

1 cup = 8 fl oz

Formula:

fl oz = cup × 8

With your value: 1 cup = 8 fl oz

How big is that?

Everyday references on a logarithmic scale, all expressed in cup (us) so you can sanity-check the result.

Milk carton (1/2.4e+2 your value)0.00423 cup

Kitchen bucket (1/24 your value)0.0423 cup

Car fuel tank (1/4.7 your value)0.211 cup

Bathtub (1/1.2 your value)0.845 cup

Your value1.00 cup

Hot tub (6.3× your value)6.34 cup

Other Cup (US) to Fluid Ounce (US) conversions

2 cup to fl oz 3 cup to fl oz 4 cup to fl oz 5 cup to fl oz 6 cup to fl oz 7 cup to fl oz 8 cup to fl oz

Cup (US) to Fluid Ounce (US) Conversion Table

Cup (US) (cup)	Fluid Ounce (US) (fl oz)
0.5	4
1	8
2	16
5	40
10	80
15	120
20	160
25	200
50	400
100	800
250	2,000
500	4,000
1000	8,000

Fluid Ounce (US) to Cup (US) Conversion Table

Fluid Ounce (US) (fl oz)	Cup (US) (cup)
0.5	0.0625
1	0.125
2	0.25
5	0.625
10	1.25
15	1.875
20	2.5
25	3.125
50	6.25
100	12.5
250	31.25
500	62.5
1000	125

Where these values come from

Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.

Cup (US) (cup)

Volume

Exact conversion

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

Source: NIST Special Publication 811, Guide for the Use of the International System of Units

National Institute of Standards and Technology (US) · Reviewed 2026-07-01

Fluid Ounce (US) (fl oz)

Volume

Exact conversion

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

Source: NIST Special Publication 811, Guide for the Use of the International System of Units

National Institute of Standards and Technology (US) · Reviewed 2026-07-01

How to Convert Cup (US) to Fluid Ounce (US)

To convert from Cup (US) (cup) to Fluid Ounce (US) (fl oz), multiply the value by 8.

Formula: fl oz = cup × 8

Reverse: cup = fl oz × 0.125

Step-by-Step Example

Start with your value in Cup (US). For example: 5 cup
Multiply by the conversion factor: 5 x 8
The result is: 40 fl oz

About Cup (US)

The US cup equals approximately 236.6 mL and is a standard cooking measurement in the United States.

Common uses: baking, cooking, recipes.

About Fluid Ounce (US)

The US fluid ounce equals approximately 29.57 mL. It is commonly used for beverage and liquid measurements.

Common uses: beverages, cooking, cocktails.

Frequently Asked Questions

How many Fluid Ounce (US) are in 1 Cup (US)?

There are exactly 8 Fluid Ounce (US) in 1 Cup (US). This means the conversion factor from Cup (US) to Fluid Ounce (US) is 8.

What is the formula to convert Cup (US) to Fluid Ounce (US)?

The formula to convert Cup (US) to Fluid Ounce (US) is: fl oz = cup × 8. For example, to convert 10 Cup (US) to Fluid Ounce (US), you would multiply 10 by 8.

What is a Cup (US)?