After researching maximum dimensions and weights permitted for carry on items of 175 airlines (only 155 of which provided specific dimensional information rather than total linear restrictions, and 13 didn’t provide weight information), I’ve concluded that a bag no bigger than 21x13x8-inches (53x33x20-cm) would only be too large for 20 of those airlines. Some of them may not care if your bag is 2 or 3-cm too big, and the likelihood of using one of those airlines is slim. In those cases, check your bag and carry what you need on the flight. I also suggest it weigh no more than 15-lbs (7-kg) when packed. That is too heavy for an additional 16 airlines that have 5 to 6-kg limits.

DUN TravelPackI’ve been searching for several years for the perfect carry on bag, and have only ever come close. Thanks to yet another project on Kickstarter, I may have found the closest option yet.