Sprocket ratio to development
Type a value in ratio to get it in m instantly.
That's 15× as tall as a sprinter’s top gear — nothing on our list beats it. At a steady 90 rpm that rolls about 793.3 km/h.
What it means
How tall is that gear?
Wheel diameters include a typical tire for each size. A fat tire adds an inch or so, which is about 3% on the gear.
The math
How to convert ratio to m
Gear inches are wheel diameter × chainring ÷ sprocket. Development follows as gear inches × π × 0.0254 meters, and gain ratio as gear inches ÷ (2 × crank length). The figures below use the wheel selected above.
Example: 70 ratio = 146.905 m.
The table below is for 700c road, 25 mm tire (26.3 in).
Every unit
Your gear in every unit
Tables
ratio to m conversion table
| ratio | m |
|---|---|
| 20 ratio | 41.9729 m |
| 30 ratio | 62.9594 m |
| 40 ratio | 83.9459 m |
| 50 ratio | 104.932 m |
| 60 ratio | 125.919 m |
| 70 ratio | 146.905 m |
| 80 ratio | 167.892 m |
| 90 ratio | 188.878 m |
| 100 ratio | 209.865 m |
| 110 ratio | 230.851 m |
| 130 ratio | 272.824 m |
m to ratio conversion table
| m | ratio |
|---|---|
| 20 m | 9.52995 ratio |
| 30 m | 14.2949 ratio |
| 40 m | 19.0599 ratio |
| 50 m | 23.8249 ratio |
| 60 m | 28.5899 ratio |
| 70 m | 33.3548 ratio |
| 80 m | 38.1198 ratio |
| 90 m | 42.8848 ratio |
| 100 m | 47.6498 ratio |
| 110 m | 52.4147 ratio |
| 130 m | 61.9447 ratio |
Quick answers
Quick answers
- How many m is 1 ratio?
- 1 ratio is 2.09865 m.
- How many m is 10 ratio?
- 10 ratio is 20.9865 m.
- How many m is 70 ratio?
- 70 ratio is 146.905 m.
The units
About these units
Sprocket ratio (ratio)
Chainring teeth divided by sprocket teeth, before the wheel is counted.
Development (m)
How far the bike travels in one full turn of the pedals.
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