Diametral pitch to module
Type a value in DP to get it in m instantly.
2.54m
That's 1.02× as coarse as a car gearbox, while a truck final drive is 2.4× coarser. A 20-tooth gear of this size would be 50.8 mm across.
Convert the other way: m to DP
What it means
How big are those teeth?
Module and pitch describe tooth size only. Gears also need the same pressure angle, usually 20°, before they will run together.
The math
How to convert DP to m
Module and diametral pitch are reciprocals through the inch: module = 25.4 ÷ DP. Circular pitch follows as CP = π × module.
Example: 10 DP = 2.54 m.
Every unit
Your tooth size in every unit
Tables
DP to m conversion table
| DP | m |
|---|---|
| 0.5 DP | 50.8 m |
| 0.8 DP | 31.75 m |
| 1 DP | 25.4 m |
| 1.25 DP | 20.32 m |
| 1.5 DP | 16.9333 m |
| 2 DP | 12.7 m |
| 2.5 DP | 10.16 m |
| 3 DP | 8.46667 m |
| 4 DP | 6.35 m |
| 5 DP | 5.08 m |
| 6 DP | 4.23333 m |
| 8 DP | 3.175 m |
| 10 DP | 2.54 m |
m to DP conversion table
| m | DP |
|---|---|
| 0.5 m | 50.8 DP |
| 0.8 m | 31.75 DP |
| 1 m | 25.4 DP |
| 1.25 m | 20.32 DP |
| 1.5 m | 16.9333 DP |
| 2 m | 12.7 DP |
| 2.5 m | 10.16 DP |
| 3 m | 8.46667 DP |
| 4 m | 6.35 DP |
| 5 m | 5.08 DP |
| 6 m | 4.23333 DP |
| 8 m | 3.175 DP |
| 10 m | 2.54 DP |
Quick answers
Quick answers
- How many m is 1 DP?
- 1 DP is 25.4 m.
- How many m is 10 DP?
- 10 DP is 2.54 m.
The units
About these units
Diametral pitch (DP)
Teeth per inch of pitch diameter, the US standard. Bigger means finer.
Module (m)
Millimeters of pitch diameter per tooth, the metric standard.
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