Estimate metres of development and speed from chainring, cog, wheel circumference, and cadence.
| Development | – |
| Speed | – |
Use this calculator to see how far the bike travels in one pedal revolution (development) and the speed that cadence would produce on flat ground with no wind. Enter chainring teeth, cog teeth, tyre circumference, and cadence.
Development = wheel circumference × (chainring ÷ cog). Speed in km/h = development (m) × cadence (rpm) × 60 ÷ 1000. A 50/14 on a 2100 mm 700c wheel is a tall road gear; 90 rpm is then a fast cruise. Circumference can be entered in millimetres (mm) or inches (in); the unit selector converts it automatically before the calculation.
Cadence is assumed constant. The result ignores wind, grade, drivetrain losses, and coasting. Development is a length per pedal turn, not a gear-inch table.
Chainring: Number of teeth on the front ring. 50 is a common large road ring.
Cog: Number of teeth on the rear cog. 14 is a small cog.
Wheel circumference: Tyre rolling circumference. 2100 mm is typical for a 700×25 road tyre. Enter mm or in.
Cadence: Pedal revolutions per minute.
Development: Distance travelled in one pedal revolution, shown in metres or feet to match the circumference unit.
Speed: Theoretical speed at the entered cadence.
Related calculators