Two numbers decide whether a backpack rides under the seat, in the overhead bin or in the hold: the airline's personal-item limit and its carry-on limit. They are different sizes, they differ by airline and by fare, and they change. That is why no bag in our range is labelled "approved" for anything. Instead, here is how to check for yourself.
1. Find today's limits for your exact fare
Search the airline's site for "carry-on size" and "personal item size" and read the page for the fare you bought. Basic-economy fares often allow a personal item only. Write both sets of dimensions down; most US carriers quote the carry-on limit at or near 22 × 14 × 9 inches and a smaller personal-item limit, but treat that as a starting point, not a rule.
2. Compare the maker's listed dimensions
Every product page here lists the maker's own height, width and depth, and a size class measured against the 22 × 14 × 9 inch reference. How the classes work. If any one dimension is over the limit on paper, plan for the bag to be checked or choose a smaller one.
3. Measure the bag packed, not empty
Soft bags grow. Pack as you will travel, stand the bag up, and measure the fullest point of each side with a tape. Compression straps and compression packing cubes bring the depth down; a stuffed outer pocket pushes it back up.
4. Decide where the laptop goes
A laptop in a padded sleeve adds depth at the back panel. If the bag will be a personal item, the sleeve is the first place to look when the depth comes out over the limit.
5. Expect the gate, not the website, to decide
Sizers at the gate and staff judgement are the final word. Leaving a little room on each dimension is cheaper than a gate-check fee.
Questions about a specific bag in our range? Ask us; we will tell you what the maker lists and whether we have measured it ourselves.