One pound of confectioners sugar is equal to 4 cups. If you want it in ounces, take 16 ounces and multiply by 2, equal 32 ounces. Although, The number of cups in an ounce will vary depending on what you’re measuring.
How many cups does one pound of powdered sugar contain?
Powdered sugar directly from the box or plastic bag weighs 4 1/2 ounces per cup; therefore, a 1-pound box (or 16 ounces) provides approximately 3 1/2 cups of powdered sugar. If a recipe asks for powdered sugar, 4 ounces of powdered sugar will equal 1 dry measuring cup.