Cycling Cadence Calculator
Convert between cadence and speed from your wheel size and gear ratio — updated live as you type.
Cycling Cadence Calculator – How It Works
The Cycling Cadence Calculator helps you understand the relationship between your pedaling cadence (RPM), riding speed, and bike gearing setup. Whether you're training for endurance, optimizing your gear choice, or simply curious about your numbers, this tool gives you instant, accurate insights.
How It Works
The calculator uses standard bicycle gear mathematics to link three key variables: cadence, speed, and your bike setup.
Core Formulas
- Wheel Circumference (in mm)
π × (rim BSD + 2 × tire width)
You can enter rim and tire sizes in millimeters or inches — the calculator handles conversion automatically. - Gear Ratio
chainring teeth ÷ cog teeth
(Example: 50/17 = 2.94) - Speed from Cadence (km/h)
speed = cadence × gear ratio × wheel circumference (mm) × 0.00006 - Cadence from Speed
The same formula solved for RPM.
Example (default values): 700×25c wheel, 50/17 gearing, 90 RPM → 33.5 km/h (≈ 20.8 mph)
Inputs
| Section | Fields |
|---|---|
| Bike Setup | Wheel preset (Road, Gravel, MTB, etc.), Rim BSD, Tire width, Chainring teeth, Cog teeth |
| Speed & Cadence | Enter either value — the other updates automatically (last edited field drives the calculation) |
Live Results (Sidebar)
- Speed in km/h and mph
- Cadence (RPM)
- Gear Ratio (e.g., 2.94:1)
- Development (meters per pedal revolution)
- Wheel Circumference (mm)
Cadence Table
See how your speed changes across different cadences (50–130 RPM in 5 RPM steps) for your current bike setup. Rows between 85–95 RPM are highlighted — this is the typical sweet spot for endurance riding.
Why This Calculator Is Better
- Live updates — no "Calculate" button needed. Results refresh instantly as you type.
- Bidirectional — change cadence or speed freely.
- Helpful presets — common wheel sizes for road, gravel, and mountain bikes.
- Smart unit conversion — toggle between mm/inches and km/h/mph.
- Extra insights — gear ratio, development, and circumference always visible.
- Practical cadence table — focused range with endurance highlighting (no more NaN errors).
Whether you're fine-tuning your training, choosing the right gears, or just exploring bike geometry, this tool makes complex cycling math simple and fast.