Involute Gear Formula
Involute gear geometry starts from module or diametral pitch, tooth count and pressure angle. The base circle defines the involute curve.
involute gear formula involute gear geometry gear tooth profile formula
Pitch diameter
d = m * z
Base circle diameter
d_b = d * cos(phi)
Why base circle matters
The involute tooth flank is generated from the base circle, so pressure angle and pitch diameter set the curve.
Related pages
- Involute gear calculator - calculate tooth geometry and profile data.
- Gear generator - generate a visual involute gear profile.
- Base circle diameter calculator - base circle and base pitch from pressure angle.
- Gear tooth calculator - tooth thickness, addendum and dedendum.