It’s happened to a lot of people – they bring their carry on onto the plane and when they try to put it into the overhead compartment, it doesn’t fit.
So they have to take the walk of shame back to the gate so they can gate check their bag. For others, you have a crabby gate attendant who insists your bag won’t fit in the overhead, even though you know darn well that it will (this one happened to me. And then it happened another time.). Either way, if you have to gate check a bag that you weren’t planning on checking, you run the risk of their breaking your stuff in it that you packed with the idea that YOU were going to handle it, not them (that one happened to me, too. It didn’t end well – I had to vacuum glass shards out of my suitcase).
But travel search engine KAYAK may have invented the solution for this problem, utilizing augmented reality (AR), with an app that measures your bag before you board, which can then be compared to the exact size requirements of your plane. Take a look at how it works: