AirPods are too big for my ears and fall out
I love the AirPods, but I my ear channel is too small for them to fit snugly. When will Apple make AirPods for kids sized ears?
iPhone 12 mini, iOS 18
Apple tries to produce AirPods that fit as many human ear variants possible. Of course the human species has too many variants to be perfect for all. Apple tries to strike a balance. AirPod Pros come with a variety of ear tips to optimize fit.
Choose your AirPods Pro ear tips and use the Ear Tip Fit Test - Apple Support
There are also third parties that sell AirPod Pro ear tips of various size.
