There are several formulas recommended. The result of each formula does not necessarily result in the same seat height. With the ball of the foot on the pedal in the six o clock position, the knee should be flexed between 25-30 degrees. Changes in seat height should not exceed more than .25 inches at a time. The seat should tilt into slight extension or be level.
Some women prefer a slight tilt forward to take pressure off of the perianal area.
This is referred to as the neutral knee position. There are various adjustments that affect upper body position and the amount of weight distributed onto the hands. While riding, elbows and knee should be separated by 1-2 inches at their closest position. Handlebars should be level or angled down toward the rear hub with a racing bike. The width of mountain bikes bars vary from 21 to 24 inches.