Bicycle Gear Calculator

Calculate gear ratios, speed, and development for your bike setup

Drivetrain Setup

Wheel Setup

Results

Speed at 90 RPM
37.4 km/h
(23.3 mph)
Gear Ratio
2.94
Gear Inches
86.8"
Development
693 cm
Wheel Circumference
235.6 cm

Common Gear Combinations

Speed (km/h) at 90 RPM for common chainring/cassette combinations

Front11T15T19T23T28T
34T39.328.822.818.815.4
39T45.133.126.121.617.7
50T57.842.433.527.722.7
53T61.345.035.529.324.1