Carry on backpacks go in the overhead bin, while personal item backpacks fit under the seat in front of you. On most flights, you're allowed one of each. Personal items must be smaller and are included free on all airlines, while some budget carriers and Basic Economy tickets charge extra for overhead bin access.

Most US airlines don't weigh carry on bags, but international airlines often do. Weight limits range from 15-22 lbs (7-10 kg) for international flights. Tortuga backpacks weigh 3.5-4.5 lbs empty, leaving plenty of room for your belongings within typical weight restrictions.

International airlines typically allow hand luggage measuring 55 × 35 × 23 cm or smaller with weight limits of 15-22 lbs. Tortuga's 40L backpacks are 55 x 35 x 23 cm (22 × 14 × 8 inches) and meet most international carry on limits. Always check your airline's hand luggage policy before flying.

Budget airlines have stricter rules and often charge for carry on bags. Spirit Airlines requires carry on bags to be 22 × 18 × 10 inches with fees starting at $37 when booked online. Ryanair allows only personal items (40 × 30 × 15 cm) for free. Always check your specific budget airline's policy and purchase carry on allowance when booking to avoid any surprise fees later.

US airlines allow carry on backpacks measuring 22 × 14 × 9 inches or smaller. Tortuga carry on backpacks measure 22 × 14 × 8 inches, fitting comfortably within these limits on all major US carriers including American, Delta, United, and Southwest.

Yes, a backpack can be a carry on if it meets airline size limits. Backpacks measuring 22 × 14 × 9 inches or smaller count as carry on luggage and can go in the overhead bin. Tortuga's 40L carry on backpacks are specifically designed to meet these requirements for hassle-free travel.