How many ounces in a cup?
1 US cup = 8 fluid ounces. For dry ingredients the weight varies — 1 cup of flour is about 4.5 oz, while sugar is about 7 oz.
The confusion comes from two different meanings of "ounce." A fluid ounce measures volume — how much space a liquid takes up. A weight ounce measures mass. For any liquid (water, milk, juice, oil), 1 cup equals exactly 8 fluid ounces, every time.
Dry ingredients are different. A cup of flour doesn't weigh the same as a cup of sugar because they pack differently. This is why serious bakers use a kitchen scale — "1 cup of flour" can vary by as much as 20% depending on how you scoop it.
The US cup is 8 fl oz (237 ml). The UK/metric cup is 250 ml — close but not identical. Most recipes mean the US standard unless stated otherwise.
In common recipes, practical conversions include butter, honey, and milk. For instance, 1 cup of butter is equivalent to 8 ounces, while 1 cup of honey weighs about 12 ounces. When measuring milk, 1 cup is approximately 8 ounces as well. These conversions are crucial for precise baking and cooking, ensuring that the right amounts are used for optimal results.
To eliminate the confusion between volume and weight, using a digital kitchen scale such as the OXO Good Grips or Ozeri can be a game changer. These scales provide measurements in grams and ounces, allowing for accurate ingredient portions regardless of their density. For example, you can weigh out 8 ounces of flour or sugar directly, rather than relying on cup measurements, which can vary slightly based on how ingredients are packed.
Key facts ¶
| 1 cup | 8 fl oz / 237 ml |
| ½ cup | 4 fl oz / 118 ml |
| ¼ cup | 2 fl oz / 59 ml |
| 1 tbsp | 0.5 fl oz / 15 ml |
| 1 pint | 16 fl oz / 2 cups |
Most people assume fluid ounces and weight ounces are interchangeable. They're not. A fluid ounce of honey weighs more than a fluid ounce of water because honey is denser — same volume, different weight. Recipes that say "4 oz flour" mean weight, not volume.
