1 cup is 8 ounces, not 16 ounces. 1 cup of liquid is equal to 8 fluid ounces in the United States. This is the standard measurement for liquid ingredients in recipes. 16 ounces is equal to 2 cups. However, there are some exceptions to this rule. For example, a cup of flour is equal to 4 ounces, and a cup of sugar is equal to 7 ounces. These measurements are used for dry ingredients, and they may vary depending on the type of ingredient.