Question: how many cups in 1 box cake mix?
Answer: A 9" round pan that is 1 1/2" deep takes 6 cups of batter, while one that is 2" deep takes 8. That's for totally full to the brim. This source says about the amount of batter from a box: An average 2-layer cake mix yields 4 to 5 1/2 cups of batter.