But what if you have neither? Can you use any kind of bag, like a backpack, as a carry-on? Yes, but it depends on the weight ...

Size and weight still matter. If you desire more creature comforts or more gear, or if you plan to be away for a long time across multiple climates, you should choose a bigger travel backpack.

The bag can be both expanded and contracted beyond this size, in case you do some shopping along the way or want to use it as a daypack. In its non-expanded form, this carry-on backpack is also ...

This backpack’s structure, padding, and size can make it feel bulky, especially if you’re not carrying much. The bag has a zippered pocket on its left strap for stashing go-to items ...