Bergdietikon has an area, as of 2006, of 6 km² (2.3 sq mi).
 Of this area, 54.6% is used for agricultural purposes, while 27.3% is forested.
 Of the rest of the land, 16.8% is settled (buildings or roads) and the remainder (1.3%) is non-productive (rivers or lakes).

The municipality is located in the Baden district on the southwest slope of the Heitersberg.
 It consists of the farm settlements of Baltenswil, Schönenberg, Herrenberg, Bernold, Kindhausen and Gwinden.

Egelsee is situated in the municipality.
Bergdietikon has an area, as of 2006, of 6 km² (2.3 sq mi).  Of this area, 54.6% is used for agricultural purposes, while 27.3% is forested.  Of the rest of the land, 16.8% is settled (buildings or roads) and the remainder (1.3%) is non-productive (rivers or lakes).
The municipality is located in the Baden district on the southwest slope of the Heitersberg.  It consists of the farm settlements of Baltenswil, Schönenberg, Herrenberg, Bernold, Kindhausen and Gwinden.
Egelsee is situated in the municipality.
Bergdietikon