The number of dry ounces in a cup can vary depending on the ingredient being measured. Unlike fluid ounces, which measure volume, dry ounces measure weight. The weight of 1 cup of a dry ingredient will depend on its density and texture. As a general guideline, 1 cup of all-purpose flour weighs approximately 4.5 to 5 ounces. However, different types of flour, such as bread flour or cake flour, may have slightly different weights. Other common dry ingredients have varying weights for 1 cup as well. For instance, 1 cup of granulated sugar weighs around 7 to 8 ounces, while 1 cup of rolled oats weighs about 3.5 to 4 ounces.