It definitely will be allowed with most if not all airlines as a carry on. I traveled to Alaska from Las Vegas on multiple planes, and never once was even questioned about it's size. It holds a decent amount of clothing, but figuring out how to pack it was a bit tricky. I initially attempted to roll all my clothing, but that proved to not hold everything. I then laid socks within the grooves of the bottom, then laid boxers flat on top of that. I then used what is called a layering method I found in a YouTube video for the pants, undershirts, and shirts. It worked, but I wasn't able to get everything in there I wanted. I estimate you can get 2 weeks of clothing in there if you are selective, and mix and match outfits. I got 3 pairs of jeans, a couple of shirts, about 6 undershirts, 6 socks, and 6 boxers in there and was able to zipper it up easily. I was going on a job at a fishing plant, so I needed to jeans to work in. O'm happy with the purchase, and will definitely be using it in the future.