My twins are 26.5 and 27.5 inches tall and my keyfit car seats have a max height of 30 inches. I thought about switching to convertible car seat since they were hating the car seat but we were on vacation last week and they hated the convertible seats we used. Yesterday, they had no issues being put in the infant car seat. Maybe they'll be in the infant car seat for a little while. We don't mind carrying them in and out of the car.