What this calculator does
The Bike Cadence and Speed Calculator estimates how fast you’re traveling based on how fast you’re pedaling (cadence), your gear setup, and your wheel size.
How the calculation works
Each pedal revolution turns the rear wheel a number of times equal to the gear ratio (chainring teeth / cog teeth). The distance covered per pedal revolution is the gear ratio multiplied by the wheel’s circumference. Multiplying that by your cadence (revolutions per minute) and then by 60 gives distance per hour, which converts to speed: Speed (km/h) = cadence x gear ratio x wheel circumference (mm) x 60 / 1,000,000.
A typical road bike wheel (700c with a standard tire) has a circumference around 2,105-2,155 mm. This calculator assumes no drivetrain slip and constant cadence, so it’s an estimate for training and gearing-planning purposes rather than an exact real-world measurement.