Oz to Cups

Fluid Ounces to Cups Conversion Formula

To convert US fluid ounces to cups, use this simple formula:

One US customary cup is defined as exactly 8 US fluid ounces. Note this is the fluid ounce of volume, not the ounce of weight (28.35 g) — for dry ingredients the weight of a cup depends on the ingredient, so this converter is for liquid volume only.

Step-by-Step Volume Conversion Guide

1. Take your volume in US fluid ounces
2. Divide it by 8 (the number of fluid ounces in one US cup)
3. Get your result in cups

Common Fluid Ounces to Cups Conversions

Practical Applications of Oz to Cups Converter

• Cooking: Turning a liquid measured in fluid ounces into cups for a recipe
• Beverages: A 16 fl oz drink is exactly 2 cups; a 32 fl oz bottle is 4 cups
• Baking: Reading US liquid measures marked in fluid ounces on the side of a jug
• Meal prep: Batch-portioning stock, broth or milk by the cup
• Nutrition: Converting serving sizes on drink labels from fl oz to cups
• Bartending: Scaling punch and cocktail batches measured in fluid ounces

History and Origin of the Cup and Fluid Ounce

The fluid ounce is a customary unit of volume; the United States defines the US fluid ounce as exactly 29.5735 ml (1/128 of a US gallon). The cup as a cooking measure was standardized in the US so that 1 cup equals 8 US fluid ounces. Beware the ambiguity: the US customary cup is 8 fl oz (about 236.6 ml), the US "legal" cup used on nutrition labels is 240 ml, and the metric cup used in Australia and parts of Europe is 250 ml. This converter uses the US customary cup of 8 fluid ounces.

Quick Conversion Tips

The math is easy because 1 cup = 8 fl oz. To convert fluid ounces to cups in your head, divide by 8: 16 fl oz ÷ 8 = 2 cups, and 4 fl oz ÷ 8 = ½ cup. Remember the milestones: 8 fl oz = 1 cup, 16 fl oz = 2 cups, and 32 fl oz = 4 cups.