Keeler is a large lunar impact crater that lies on the Moon's far side.

To the northeast of Keeler is the smaller crater Stratton, and to the northwest lies Ventris.

The outer rim of Keeler is roughly circular, with a straight segment where it is joined to Heaviside.

[3] The crater was named after American astronomer James Edward Keeler by the IAU in 1970.

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