depends. i can get away with my 45. i can fit my makeup and toiletries and stuff, as well as 1 or two pairs of jeans, a hair dryer, 2 pairs of shoes, a bag or two, and a few shirts. i make it work, because i'm usually treking through nyc and don't want to have to carry more than one bag. and this is usually for a 2/3 night trip, from friday - sunday although it could make it through till monday. i usually have enough clothes with me.