How do I choose a travel backpack for carry-on trips?

The best travel backpack is the one that fits your body and your trip. REI’s backpack guide says torso length matters more than height, and its luggage guide says the right bag size depends on trip length, packing habits, and whether you want to stay within carry-on limits. That is the main filter: fit first, volume second, features third.

For carry-on-only travel, do not oversize the pack just because you like extra room. REI notes that most airlines allow carry-on bags no larger than 45 linear inches when you add length, width, and height, and that the rules vary by airline. In practice, a 35- to 45-liter travel pack is usually the sweet spot if you pack reasonably light.

Then pick features that match your routine. Travel packs are good when you want organization pockets, hideaway straps, and easy movement through airports, train stations, and stairs. Wheeled luggage is better if you mostly roll through smooth terminals, but a backpack is better if your trip includes cobblestones, transit, or stairs. If you never want to check a bag, look for a pack that is comfortable when fully loaded, not just one that looks tidy in a product photo.

If you want to shop now, start with a travel backpack. For packing context, compare it with how to choose a carry-on bag, how to choose a travel toiletry bag, and how to pack a carry-on bag for a weeklong trip.