Tolansky is a small, circular lunar impact crater that is located due south of the crater Parry on the Mare Cognitum.

The formation is symmetric, with a light-hued outer rim and a darker interior floor.

A rille belonging to the Rimae Parry almost connects with the north-northwestern rim of Tolansky.

It was named after British physicist Samuel Tolansky.

[1] It was formerly known as Parry A, prior to its current name being approved by the IAU in 1976.