Bike Cadence and Speed Calculator
Enter your gear combination, wheel size, and cadence to see your cycling speed instantly in both km/h and mph. Switch to reverse mode to find the pedaling rate needed to hit a target speed. You also get gear ratio, wheel rollout, and a breakdown table showing speed across eight common cadences.
Formula
Worked example
A 50/17 gear on a 700c x 25 mm tyre: rim BSD = 622 mm, outer diameter = 622 + 50 = 672 mm, rollout = pi x 0.672 = 2.111 m, development = 2.111 x (50/17) = 6.21 m. At 90 rpm: 6.21 x 90 x 60 / 1000 = 33.5 km/h (20.8 mph).
What cadence and speed mean in cycling
Cadence is the rate at which you turn the pedals, measured in revolutions per minute (rpm). Speed is how fast the bike moves across the ground. The two are linked through your gear combination and wheel size: for any given gear, every extra rpm adds a fixed increment of speed. A 50/17 combination on a 700c x 25 mm wheel advances you about 6.2 m per pedal stroke. At 90 rpm that works out to around 33.5 km/h; at 100 rpm the same gear takes you to roughly 37.2 km/h. Understanding this relationship helps you choose the right gear on the fly, plan training zones, and compare gearing setups before you buy.
How the calculation works
The calculator uses the tyre outer diameter, which is the rim bead seat diameter (BSD) plus twice the tyre section width. Multiplying by pi gives the wheel rollout (circumference) in metres. The gear ratio (chainring teeth divided by rear cog teeth) tells you how many times the wheel rotates for each pedal revolution. Gear development = rollout x gear ratio, the distance covered per pedal stroke. Speed = development x cadence (converted from rpm to rev/s). In reverse mode, the calculator divides target speed by development to get the required rpm. All calculations use standard physics, so results match real-world GPS data when tyre pressure and size are accurate.
Choosing the right cadence for your riding
Research consistently shows that most cyclists perform best between 80 and 100 rpm for sustained efforts. Grinding below 70 rpm puts more torque through the knees and fatigues the muscles faster than it should for the power produced. Spinning very high cadences (above 110 rpm) increases cardiovascular load without much mechanical advantage on flat roads. The sweet spot for most road cyclists is 85-95 rpm on flat to rolling terrain, dropping slightly on steep climbs where momentum and leverage change. Track sprinters can peak above 160 rpm for a few seconds, but that is not sustainable and requires very high neuromuscular coordination.
Gear selection and gear development explained
Gear development is the single most useful number when comparing gearing setups. It tells you the ground covered per pedal stroke regardless of wheel size, so you can directly compare a 50/17 on 700c against a 48/16 on 650B. A higher development means faster speed for the same cadence but harder pedaling. Most road bikes cover a development range from about 2 m (lowest climbing gear) to 9-10 m (hardest top gear). Time trial bikes often have a tighter range focused on 5-7 m for race pace. Matching development to your cadence preference and the terrain is the core skill of gearing selection.
Cycling cadence zones
| Cadence (rpm) | Zone | Typical use |
|---|---|---|
| < 60 | Grinding | Steep climbs in a too-hard gear |
| 60-70 | Low | Climbs, heavy loads, beginners |
| 70-80 | Moderate | Recreational riding, steady climbs |
| 80-90 | Optimal low | Endurance and long-distance riding |
| 90-100 | Optimal high | Road cycling, time trials, efficient cruise |
| 100-110 | High | Spirited riding, light flat terrain |
| 110-120 | Very high | Sprinting, velodrome, downhill spinning |
| > 120 | Sprint | Short sprint efforts, track racing |
Common cadence ranges and their typical applications, based on coach guidelines and sport science research.
Frequently asked questions
What is a good cycling cadence?
Most coaches recommend 80 to 100 rpm for sustained road cycling. Research by Takaishi et al. and others shows that self-selected cadences in this range minimise muscular fatigue relative to the power produced. Beginners often naturally pedal at 60-70 rpm; developing a higher cadence takes practice but reduces knee stress and improves oxygen efficiency over long rides. Track sprinters can exceed 120 rpm for short bursts, while climbers sometimes drop to 70-80 rpm on very steep gradients.
How is cycling speed calculated from cadence?
Speed = gear development x cadence, where gear development = wheel circumference x gear ratio. Wheel circumference = pi x (rim BSD + 2 x tyre width). Gear ratio = chainring teeth / rear cog teeth. For example, a 50/17 gear on a 700c x 25 mm tyre has a development of about 6.21 m. At 90 rpm that gives 6.21 x 90 = 558.9 m/min = 33.5 km/h.
What is gear development and why does it matter?
Gear development is the distance your bike travels for each complete pedal revolution. It accounts for both the gear ratio and the wheel size, so it lets you compare bikes with different wheel sizes directly. A higher development means more distance per stroke, which is faster at the same cadence but requires more force. Knowing your development helps you choose gearing before a sportive or race, match your setup to the expected terrain, and understand how a new cassette or chainring change will feel.
What is the difference between gear ratio and gear development?
Gear ratio is simply chainring teeth divided by cog teeth (e.g. 50/17 = 2.94). It tells you how many times the wheel rotates per pedal turn. Gear development multiplies the gear ratio by the wheel circumference to give metres per pedal stroke. Development is more practical because it is independent of wheel size: a 2.94 ratio means different things on a 26" bike versus a 700c bike, but equal development always means equal speed at equal cadence.
How does tyre width affect speed?
A wider tyre increases the effective rolling diameter, which slightly increases wheel circumference and therefore speed at the same cadence and gear. The difference is small in practice: going from a 25 mm to a 28 mm tyre on a 700c rim increases rollout by about 19 mm (roughly 0.9%), adding around 0.3 km/h at 90 rpm in a 50/17 gear. However, tyre width affects rolling resistance and comfort, which can indirectly influence average speed much more significantly over a long ride.
What chainring and cog should I use for a given speed?
Use the reverse mode of this calculator: enter your target speed and the calculator tells you the required cadence for your current gear. If the resulting cadence is too high or too low, adjust your cog size. A larger rear cog (more teeth) reduces cadence for the same speed, making the gear easier. A smaller rear cog increases cadence, making the gear harder. Most road bikes let you adjust cog size in 1-2 tooth increments within a cassette, giving fine-grained control over cadence at any given speed.
Sources
- Takaishi T, Yamamoto T, Ono T, Ito T, Moritani T. Neuromuscular, metabolic, and kinetic adaptations for skilled pedalers. Med Sci Sports Exerc. 1998.
- Nimmerichter A, Williams C, Bachl N, Eston R. Evaluation of a field test to assess performance in elite and non-elite cyclists. Int J Sports Med. 2010.