Carry-on luggage size restrictions vary by airline-here's how to tell if your suitcase, backpack, or duffle bag is small enough to bring as a carry-on.

Airlines calculate carry-on luggage size measurements using two methods: Height by width by depth: Most – but not all – airlines measure bags by inches or centimeters using this formula ...

As for carry-on bags, those are an entirely different world of fees and size restrictions – you can find information for major American and international airlines in a separate U.S. News guide ...

A good carry-on bag is one that fits your airline’s size requirements, but also offers you some perks to make your life easier, like a USB charging port for your devices or built-in organizers ...