There is no standard size restriction for carry-on bags, since different planes come with varying overhead and under-the-seat allowances. According to the FAA (Federal Airline Administration), the maximum size carry-on bag for most airlines is 45 linear inches (the total of the height, width, and depth of the bag), while being no longer than 22 inches. Anything larger should be checked.
Here are the top pieces of carry-on luggage, according to Real Simple:
Winner: VICTORINOX WERKS TRAVELER UPRIGHT, $260. It's made by the same company that manufactures the Swiss Army knife. Its features include a suiter, two snap-in mesh packing cubes that maximize the awkward space between the bars at the bottom of the bag, and inline-skate wheels. www.horchow.com
Runner-up: TRAVELPRO CREW 6 SUITER, $199. It's a Teflon-coated lightweight bag, and its features include a toiletry bag, a suiter, and a water-resistant lining. It's available at Macys.
Winner: LL BEAN ROLLING ADVENTURE DUFFEL, $79.50. It opens wide for easy packing, and it has wheels, a telescoping handle, and a padded shoulder strap that make it easy to maneuver. www.llbean.com
Runner-up: HALSEA WEEKEND BAG, $225. It's made of durable laminated canvas and it has a leather bottom with five metal feet. www.halsea.com
Winner: BARBOUR CANVAS TRAVEL EXPLORER, $299. The 113-year-old Barbour company made its name protecting Scottish fishermen from the elements. Its tote is coated in stain-resistant Teflon and laminated for water-resistance. To find a store that carries it, call 800-338-3474.
Runner-up: UTILITY CANVAS OVERNIGHTER BAG, $112. This bag, designed by a married couple, has a rubbery bottom designed to protect against wear, and three exterior pockets provide easy access to in-flight essentials. www.utilitycanvas.com
Winner: LANDS' END LIGHTHOUSE BACKPACK, $65. There's a padded section for a laptop and plenty of pockets, both inside and out. It's also small enough to slide under the seat in front of you. www.landsend.com
Runner-up: TUMI SPORT BACKPACK, $195. It's made of high-tech nylon and plenty of pockets, including an interior iPod pocket with an opening to accommodate headphones. www.tumi.com