About the Gear Module Calculator
Gear module from pitch diameter and teeth, with the centre distance for a meshing pair.
Also known as: module from diameter, metric gear module, diametral pitch converter, gear centre distance.
How to use this calculator
- Enter i know the, teeth on the mating gear and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
module = pitch diameter ÷ number of teeth = 25.4 ÷ DP
Worked example
Using the values pre-filled in the calculator above:
- I know the: Pitch diameter and teeth
- Pitch diameter = 80 mm
- Teeth = 40
- Teeth on the mating gear = 20
the calculator returns:
- Module: 2 mm
- Diametral pitch: 12.7 DP
- Circular pitch: 6.2832 mm
- Nearest standard module: 2 mm