Luggage brought onto airplanes may measure no more than 45 linear inches for carry-on baggage and 62 linear inches for checked baggage, which can weigh no more than 50 pounds. Linear inches are the sum of the three dimensions of the bag.
Many airlines restrict the dimensions of carry-on bags to 22 inches by 14 inches by 9 inches with a weight of less than 40 pounds. Dimensions of checked baggage are limited to 27 inches by 21 inches by 14 inches.
In addition to one piece of carry-on baggage per passenger, most airlines allow one personal item, including briefcases, handbags, laptop computers and small book bags.
Most airlines allow oversized and overweight checked bags for a fee.