Crowned splines are internal or external gears located at the top end of a shaft, rod or bearing and are typically in-volute splines.

These splines have crowned teeth to compensate for angular misalignment between the shaft and the mating detail.

Usual in-volute splines can handle a 2-degree misalignment; however, in-volute crowned splines can handle up to 5 degrees. Their design decreases the stress concentration thus increasing its strength and reducing the possibility of cracks through fatigue.