Traveling by air soon? Please make sure your carry on does not exceed the maximum allowed dimensions. Most major US airlines allow you to bring 1 carry on bag and 1 extra personal item. Your personal item should be stored under the seat in front of you. Usually they allow items like: a shoulder bag, a backpack, laptop bag, a briefcase, a camera, a diaper bag, or an other small item. Most airlines in the United States allow your carry on bag size total to be 45?, that would be a 22? x 14? x 9? suitcase. Still not sure what you can bring on board of an airplane? Check our website at carryonsize.net to see for yourself.