Ideler is a small lunar impact crater in the low southern latitudes of the Moon.

This formation is visible from the Earth, but it appears somewhat foreshortened due to its location.

The smaller satellite crater Baco R is nearly attached to the opposite, western rim.

It is named for the German astronomer Christian Ludwig Ideler.

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