It lies to the south of the crater H. G. Wells and to the southeast of Cantor.

The inner wall varies in width, with the narrowest stretch along the outward-bulging northeast.

The interior floor is uneven, with a central ridge that runs to the southern edge.

Prior to formal naming by the IAU in 1970,[1] Kidinnu was called Crater 122.

[2] By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Kidinnu.