Cycling Cadence Calculator
Calculate cycling cadence from speed, gearing and wheel size, and find the gear for a target cadence.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
This is a gearing calculation from speed, wheel and tire size, chainring teeth, and rear sprocket teeth. It estimates cadence and development; it does not assess rider comfort, fitness, or knee load.
Worked example
calculated with the default values below
Speed 18 mph · Chainring teeth 50 · Cassette teeth 17 · Wheel size 700c road (28 in) · Tyre width 25 mm · Target cadence 90 rpm Current cadence 77.8 rpm · Gear ratio 2.94 · Distance per pedal revolution 6.21 m · Speed at your target cadence 20.8 mph · Theoretical rear sprocket teeth 19.7
General background references
Disclaimer
These calculators give general mathematical results. They suit study, planning and estimation — verify anything that feeds a graded submission, a published figure or a financial commitment.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
Cad = v × 1609.344 ÷ 60 ÷ (π × (D + 2t) ÷ 1000 × F ÷ R)
- v
- Speed (mph)
- D
- Rim diameter (mm)
- t
- Tire width (mm)
- F
- Front chainring teeth
- R
- Rear sprocket teeth
Rim presets: 700c/29″ = 622, 650b = 584, 26″ = 559, 20″ = 406; speed at target cadence = Cad × development × 60 ÷ 1609.344.
Frequently asked questions
Why does wheel size change the cadence at a given speed?
Cadence depends on wheel circumference, which the tool derives from rim diameter plus twice the tyre width. A 700c rim is 622 mm, so with a 25 mm tyre the circumference is about 2.11 m; a 20-inch rim of 406 mm drops it to about 1.46 m, raising cadence for the same speed by roughly 44 percent. Tyre width therefore matters more than many riders expect.