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Cups to Oz Converter

Not sure how many ounces are in a cup? Whether you're scaling a recipe or checking a measurement — get the instant answer plus a free calculator and full chart.

⚡ Quick Answer
1 US cup = 8 fl oz. To convert cups to ounces, multiply by 8. Example: 2.5 cups × 8 = 20 fl oz.

Cups to Oz Converter

8
US fluid ounces
Oz to Cups Converter
1
US cups
cups → oz: fl oz = cups × 8  |  oz → cups: cups = fl oz ÷ 8

Common Cups to Oz Conversions

These are the most frequently needed cups-to-ounces values for cooking, baking, and beverage preparation:

  • ¼ cup to oz: 0.25 × 8 = 2 fl oz
  • ⅓ cup to oz: 0.333 × 8 = 2.67 fl oz
  • ½ cup to oz: 0.5 × 8 = 4 fl oz
  • ⅔ cup to oz: 0.667 × 8 = 5.33 fl oz
  • ¾ cup to oz: 0.75 × 8 = 6 fl oz
  • 1 cup to oz: 1 × 8 = 8 fl oz
  • 1.5 cups to oz: 1.5 × 8 = 12 fl oz
  • 2 cups to oz: 2 × 8 = 16 fl oz (1 pint)
  • 4 cups to oz: 4 × 8 = 32 fl oz (1 quart)
  • 8 cups to oz: 8 × 8 = 64 fl oz (½ gallon)
  • 16 cups to oz: 16 × 8 = 128 fl oz (1 gallon)

Cups to Oz Conversion Chart

Full reference table covering fractions of a cup through 16 cups (one gallon):

Cups (c)Fluid Oz (fl oz)Milliliters (mL)Equivalent
⅛ cup1 fl oz29.57 mL2 tbsp
¼ cup2 fl oz59.15 mL4 tbsp
⅓ cup2.67 fl oz78.86 mL5 tbsp + 1 tsp
½ cup4 fl oz118.3 mL8 tbsp
⅔ cup5.33 fl oz157.7 mL10 tbsp + 2 tsp
¾ cup6 fl oz177.4 mL12 tbsp
1 cup8 fl oz236.6 mL16 tbsp
1¼ cups10 fl oz295.7 mL
1½ cups12 fl oz354.9 mL
1¾ cups14 fl oz414.0 mL
2 cups16 fl oz473.2 mL1 pint
3 cups24 fl oz709.8 mL
4 cups32 fl oz946.4 mL1 quart
6 cups48 fl oz1,420 mL
8 cups64 fl oz1,893 mL½ gallon
12 cups96 fl oz2,839 mL¾ gallon
16 cups128 fl oz3,785 mL1 gallon

How to Convert Cups to Ounces

The conversion is a single multiplication — and one of the easiest in the US customary system:

fl oz = cups × 8   |   cups = fl oz ÷ 8

The number 8 comes from the US customary hierarchy: 1 cup = 8 tablespoons × 2 = wait — more directly, the cup is defined as ½ pint, and 1 pint = 16 fl oz, so 1 cup = 8 fl oz. Clean, consistent, easy to remember.

Examples

  • Convert 3.5 cups: 3.5 × 8 = 28 fl oz
  • Convert 20 fl oz to cups: 20 ÷ 8 = 2.5 cups
  • Convert 6 cups to gallons: 6 cups = 48 fl oz ÷ 128 = 0.375 gallons

For gallon-scale conversions from fluid ounces, use our oz to gallon converter.

Kitchen Uses & Practical Examples

Scaling Recipes

When a recipe calls for "2 cups of broth" and your measuring equipment only shows fl oz, you need 16 fl oz. If you're doubling the recipe: 4 cups = 32 fl oz — which is exactly one 32 oz carton of broth. Knowing cups-to-oz instantly removes the guesswork.

Beverage Preparation

Standard US drinking glasses hold 8–16 fl oz (1–2 cups). A typical pitcher holds 2 quarts (64 fl oz = 8 cups). When making a batch of lemonade for 8 people at 8 fl oz each, you need 64 fl oz — exactly 8 cups or half a gallon.

Baking Precision

Liquid ingredients in baking — milk, buttermilk, cream, oil — are almost always measured by volume (fl oz or cups). When converting a recipe that uses one unit system to another, cups-to-oz is your most-used conversion. A ¾ cup of milk = 6 fl oz every time, no matter the recipe source.

Cups in the US Volume Hierarchy

Understanding where the cup sits in the broader measurement system makes all conversions easier:

1 gallon (128 fl oz)
  = 4 quarts (32 fl oz each)
  = 8 pints (16 fl oz each)
  = 16 cups (8 fl oz each)
  = 256 tablespoons (½ fl oz each)

This hierarchy means: 16 cups = 1 gallon. So if a recipe calls for 16 cups of liquid, that's a full gallon. Use the gallon to oz tool for large-batch scaling.

For a complete reference of all liquid unit relationships, see: Liquid Measurement Conversion Chart.

Official US customary volume definitions: National Institute of Standards and Technology (NIST).

Frequently Asked Questions

How many oz in a cup?
1 US cup = 8 US fluid ounces. This is the standard used in all American measuring cups and recipes.
How many oz in 2 cups?
2 cups = 16 fl oz (2 × 8 = 16). This is also equal to 1 US pint.
How many cups is 32 oz?
32 fl oz = 4 cups (32 ÷ 8 = 4). 32 oz is also equal to 1 US quart.
How do you convert cups to ounces?
Multiply cups by 8. Formula: fl oz = cups × 8. Example: 3 cups × 8 = 24 fl oz.
Is a dry cup the same as a liquid cup?
By volume, yes — both equal 8 fl oz (236.6 mL). However, the weight of a "cup" varies by ingredient. A cup of flour weighs about 4.5 oz; a cup of water weighs about 8.3 oz.
How many cups in a gallon?
There are 16 cups in 1 US gallon (128 fl oz ÷ 8 fl oz per cup = 16 cups).