Cycling Cadence to Speed Calculator

Cycling cadence and rollout speed

Cadence is your pedalling rate, in revolutions per minute (rpm). Most road cyclists sit at 80–100 rpm on flat ground, while track sprinters and time-trialists can spin past 120 rpm in short bursts. Speed comes from cadence multiplied by the rollout, meaning the metres you travel per crank revolution. The relationship is v = cadence · rollout, where rollout = (chainring / sprocket) · π · wheel diameter.

The chainring/sprocket ratio, what imperial units call gear inches, sets how far the bike travels per stroke. A 50×15 on a 700c wheel (≈2.13 m circumference) rolls out 7.10 m per revolution, and at 90 rpm that works out to 38.4 km/h. Lance Armstrong made the high-cadence climbing style famous at the 1999 Tour de France, pulling the peloton away from grinding big gears. Mechanical power is torque times angular velocity (P = τ · ω). Modern power meters from Garmin, Wahoo and SRM split that product apart, which lets coaches set targets for both cadence and force.

Applications

Bike fitters lean on rollout to pick chainring sizes for a target speed. Criterium racers drill cadence above 110 rpm so they can react to attacks, and indoor trainers like Zwift and TrainerRoad show cadence right beside power on every interval. The same formula sizes the gearing on fixed-gear track bikes, which run a single ratio and never coast.

FAQ

Is high cadence always better? Not really. You are trading muscular load for cardiovascular load. Time-trialists like Filippo Ganna often settle near 95 rpm to balance the two.

How is cadence measured? The classic setup was a magnet on the crank arm with a sensor on the chainstay. These days most cyclists run accelerometer-based sensors on the pedal or crank, paired to head units over ANT+ or Bluetooth.

Does wheel size really matter? It does. A 650b gravel wheel rolls less per turn than a 700c, so the same gear pushes a slightly lower speed at the same cadence. The calculator above takes any wheel diameter, so you can match your own setup.