This car seat can be used until the child reaches either 35 lbs (15.8 kg), 32 inches (81 cm), or the top of their head is less than 1 inch (2.5 cm) below the top of the headrest or car seat shell, whichever is taller. Once your child reaches any of these three measurements your child has outgrown the car seat and will need to transition to a convertible or all-in-one car seat in rear-facing mode.