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Bike Cadence and Speed Calculator.

Calculate bicycle speed from pedal cadence, wheel diameter, and gear ratio.

On-device calculationNo signup
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Set your values

Results update as you type.

Speed (km/h): 23.75044

Speed (km/h)

0.000000
Wheel RPM: 180

Wheel RPM

0.000000
Wheel circumference (m): 2.199115

Wheel circumference (m)

0.000000

Results update automatically as you type.

Use Cases

Estimate speed for training

Use this calculator to estimate your speed at a given cadence and gear, helping you plan training rides or understand your pace.

Example: If you pedal at 90 rpm with a 700c wheel (0.7 m diameter) and a gear ratio of 3.5, your speed is about 41.6 km/h.

Compare gear setups

Experiment with different gear ratios and cadences to see how they affect your speed, useful for choosing gears for different terrains.

Example: Try a higher gear ratio (e.g., 4.0) at the same cadence to see a speed increase.

Frequently Asked Questions

How does the bike cadence and speed calculator work?
This calculator estimates your bike speed by multiplying your pedaling cadence (in rpm) by the wheel circumference (derived from wheel diameter) and the gear ratio (front teeth divided by rear teeth). The result is your speed in the units corresponding to your inputs.
What is gear ratio and how do I find it?
Gear ratio is the number of teeth on the front chainring divided by the number of teeth on the rear cog. For example, if your front has 50 teeth and rear has 12, the ratio is 50/12 ≈ 4.17. You can usually find these numbers printed on the components.
Can I use this calculator for any bike?
Yes, as long as you know your cadence, wheel diameter in meters, and gear ratio. It works for road bikes, mountain bikes, and other bicycles. Just ensure you use consistent units (e.g., wheel diameter in meters) for accurate results.

Tips & Common Mistakes

Tips

  • Measure your wheel diameter accurately: for a 700c wheel, the diameter is about 0.7 m, but check your tire size for precision.
  • Use a consistent unit system: if you enter wheel diameter in meters, your speed will be in meters per minute; convert to km/h or mph as needed.
  • Cadence is the number of pedal revolutions per minute; a typical cadence for road cycling is 80-100 rpm.
  • Remember that this calculator assumes a constant gear ratio; if you change gears, recalculate.

Common Mistakes to Avoid

  • Using wheel circumference instead of diameter: the calculator expects diameter, not circumference. If you have circumference, divide by π (3.14) to get diameter.
  • Forgetting to convert units: if you enter wheel diameter in inches, the speed will be in inches per minute, which is not practical. Convert to meters first.
  • Mixing up gear ratio: ensure you divide front teeth by rear teeth, not the other way around.

Last updated: August 13, 2026