Convert between cycling cadence (RPM), speed, and gear ratio. Find the perfect balance of pedaling rate and velocity for any terrain.
The relationship between cadence and speed is fundamental to cycling performance. Your speed on a bike is determined by three factors: how fast you pedal (cadence), what gear you're in (gear ratio), and the size of your wheels. Understanding this relationship helps you make smarter gear choices and develop more efficient pedaling habits.
This calculator works in both directions — enter a target speed to find the required cadence, or enter a cadence to discover what speed you'll achieve. It accounts for different wheel sizes, tire widths, and the full range of modern drivetrain gearing options from compact road to wide-range mountain bike setups.
Elite time trialists often ride at specific cadence-speed combinations that they've determined through lab testing and race experience. Recreational cyclists benefit from understanding these relationships too, especially when planning routes with varying terrain. Knowing that a 6% climb at 12 km/h requires 75 RPM in your easiest gear helps you decide if you need a wider cassette range before tackling mountainous routes.
This calculator eliminates guesswork in gear selection and pacing strategy. Whether you're preparing for a race, planning training zones by speed, or choosing components for a new build, knowing the exact cadence-speed relationship helps you make informed decisions. Keep these notes focused on your operational context. Tie the context to the calculator’s intended domain. Use this clarification to avoid ambiguous interpretation.
Speed (km/h) = Cadence × Gear Ratio × Wheel Circumference × 60 / 1000. Cadence (RPM) = Speed (km/h) × 1000 / (Gear Ratio × Wheel Circumference × 60). Where Gear Ratio = Front Teeth / Rear Teeth.
Result: 33.1 km/h (20.6 mph)
With a 52/15 gear ratio (3.47) on 700×25c wheels (2.105m circumference), pedaling at 90 RPM produces a speed of 33.1 km/h. This is a typical road race tempo.
Every cycling speed is the product of cadence and gear development (gear ratio × wheel circumference). This means there are infinite cadence-gear combinations that produce the same speed. A rider doing 30 km/h could be spinning 110 RPM in a 39/19 gear or grinding 65 RPM in a 53/17 gear. The physiological cost of these two approaches is vastly different, which is why cadence management matters.
Road racers use cadence-speed knowledge to select ideal gearing for time trials, where every watt counts. A triathlete might determine that their target race speed of 37 km/h requires 88 RPM in their 52/15 gear — and then train specifically at that cadence to build efficiency. Mountain bikers use these calculations to verify that their lowest gear provides a manageable cadence on their steepest local climb. Commuters can determine the single optimal gear for their flat daily route.
The shift from 2× to 1× drivetrains in mountain biking and gravel riding has changed cadence-speed calculations significantly. A 1×12 setup with a 32T chainring and 10-52T cassette provides gear ratios from 0.62 to 3.20 — a 520% range. This compares to roughly 575% for a 2×11 road setup (34/50 × 11-32). The wider jumps between gears in 1× systems mean less precise cadence control, which matters most at race-pace speeds where a few RPM difference affects power output.
It depends on gearing. In a 50/17 gear (2.94 ratio) on 700×25c wheels, you'd need about 80 RPM. In a 39/17 gear, you'd need about 103 RPM.
Tire pressure slightly changes the effective rolling circumference — lower pressure creates more tire deformation. The difference is typically less than 1%, so standard circumference values are accurate enough for cadence calculations.
Not necessarily. Higher cadence at the same gear means more speed, but it also increases cardiovascular demand. The fastest speed comes from the right balance of cadence and gear for your fitness level.
Tour riders typically pedal at 90-100 RPM on flat stages, 80-95 RPM on climbs, and 100-120 RPM in sprints. Individual preferences vary — some riders naturally favor higher or lower cadences.
Count your pedal strokes for 15 seconds and multiply by 4. Or use this calculator in reverse — enter your known speed and gearing to determine your cadence.
Yes. Most cyclists experience cadence drift (gradual decline) during long rides as neuromuscular fatigue sets in. Training specifically at target cadences helps maintain consistency.