π΄ Bike Cadence to Speed Calculator
Enter your cadence and gearing to see exactly how fast the bike moves.
Speed at This Cadence and Gear
For informational purposes only, not medical advice. Consult a healthcare professional.
How to Use This Cadence to Speed Calculator
Your speed on a bike is pure mechanics: how fast your legs spin, multiplied by how far the bike travels per pedal revolution. Enter your cadence in revolutions per minute, your chainring and rear cog tooth counts, and your wheel size. The calculator returns your speed in mph and km/h, plus the gear inches cyclists use to compare gearing across bikes.
Enter your cadence in RPM. Most recreational riders spin 70 to 90; trained riders hold 85 to 100.
Enter your front chainring teeth and rear cog teeth for the gear you are in. A 50x16 is a typical flat-road cruising gear on a road bike.
Pick your wheel size. The rollout circumference matters: bigger wheels travel farther per revolution.
Read your speed. Then change the cog by one or two teeth to see exactly what one shift is worth at the same cadence.
The Formula: Cadence Times Gear Times Wheel
Each pedal revolution turns the rear wheel (chainring / cog) times, so a 50x16 spins the wheel 3.125 times per crank turn. Each wheel turn moves the bike forward one circumference, 2105 mm for a 700x25c tire. Multiply by cadence and by 60 minutes, convert millimeters to kilometers, and you have speed. Gear inches is the traditional alternative: it imagines the gear as a direct-drive penny-farthing wheel of that diameter, which lets riders compare a road bike and a mountain bike on one scale. The math is exact; wind, hills, and rolling resistance decide how much power that speed costs, not whether the speed is real.
Worked Example
Enter cadence 90 RPM, chainring 50, cog 16, and a 700x25c wheel at 2105 mm. Gear ratio = 50/16 = 3.125, so each pedal turn spins the rear wheel 3.125 times. Wheel revolutions per minute = 90 x 3.125 = 281.25. Distance per minute = 281.25 x 2105 mm = 592,031 mm, and per hour that is 35,521,875 mm, or 35.52 km/h. Convert to miles: 35.52 / 1.609344 = 22.07 mph. Gear inches = 3.125 x (2105/25.4) = 259.0. The calculator shows these same figures. Drop one cog tooth to a 15 and the same 90 RPM gives 23.5 mph, which shows why gear choice matters as much as leg speed.
What Cadence Should You Ride?
Beginners usually mash big gears at 60 to 70 RPM because it feels powerful, but research and coaching experience point to 85 to 95 RPM as the efficient band for most riders: it spreads the work across more pedal strokes, sparing the knees and delaying muscular fatigue. Climbing naturally drops cadence to 65 to 80 as gears run out, which is fine. If your cadence sits under 75 on flat ground, shift to an easier gear and spin faster at the same speed; it will feel strange for two weeks, then normal. Triathletes often target the low 90s to save their legs for the run. Track cadence with a cheap crank sensor if your bike computer supports it, since perceived cadence is usually 10 RPM higher than reality.
Gearing Choices Explained
Compact cranksets (50/34) paired with wide cassettes (11-34) give beginners and climbers low gears for hills without sacrificing top-end speed. Standard 53/39 setups suit strong flat-land riders. One tooth on the rear cog changes speed about 6 percent at fixed cadence, which is why cassettes with single-tooth jumps feel so smooth. When comparing bikes, gear inches beat raw tooth counts because they include wheel size: a 32x16 on a 29er and a 50x25 on a road bike can be nearly the same gear. Use the calculator to check that your easiest gear is truly easy enough for the steepest hill you ride.
Second worked example: climbing gear at 75 RPM
Enter cadence 75 RPM, chainring 34, cog 28, and the same 700x25c wheel at 2105 mm. Gear ratio = 34/28 = 1.2143. Wheel revolutions per minute = 75 x 1.2143 = 91.07. Distance per minute = 91.07 x 2105 mm = 191,704 mm, per hour 11,502,240 mm = 11.50 km/h, which is 7.15 mph. Gear inches = 1.2143 x 82.87 = 100.6. Compare with the first example: 90 RPM in 50x16 gave 22.07 mph, while 75 RPM in 34x28 gives 7.15 mph. Same calculator, same physics, and the reason your climbing gear exists.
Now change only the cog to 25 and watch one shift: ratio 34/25 = 1.36, speed = 75 x 1.36 x 2105 x 60 / 1,000,000 = 12.88 km/h. One shift at the same cadence is worth 1.38 km/h on the climb, about 12 percent. That is why cassettes with single-tooth jumps feel so much smoother than wide-range ones: the steps between gears stay small.
Cadence drills that work
Three drills fix a slow cadence. Spin-ups: in an easy gear, gradually raise cadence over 60 seconds until you bounce, hold 5 seconds, recover 2 minutes, repeat 4 to 6 times. Isolated-leg training: unclip one foot (on a trainer), pedal 30 seconds with the other, focusing on scraping through the bottom of the stroke; the dead spots in your pedal stroke become obvious fast. High-cadence holds: 5 x 3 minutes at 100 to 110 RPM in an easy gear with 3 minutes recovery. Do one drill session weekly for a month and 85 RPM starts feeling like your natural rhythm instead of a chore.
Common cadence mistakes
Mistake one is bouncing. If your hips rock at 95 RPM, the gear is too easy or your core is not stabilizing; drop 5 RPM and build back up. Smooth first, fast second. Mistake two is mashing into headwinds and climbs in the same gear you use on flats. Shift early and often: the goal is constant cadence, variable gear, not the reverse. Mistake three is copying pro cadences from race footage. Pros spin 95 to 105 RPM because their aerobic engines support it; forcing 100 RPM on an untrained engine just spikes heart rate. Ride 85 to 90, train the engine, and let cadence rise with fitness.
For informational purposes only, not medical advice. Consult a healthcare professional.
A Second Worked Example: The Fast Group Ride
A group ride rolls at 24 mph and you want to know the cadence. Rearrange the formula: cadence equals speed divided by (gear ratio times wheel circumference times 60). Take a 50x14 gear: 50 divided by 14 is 3.571. A 700x25c wheel travels about 2.105 meters per revolution. Speed 24 mph is 10.73 meters per second. Cadence in revs per second is 10.73 divided by (3.571 times 2.105), which is 10.73 divided by 7.517, or 1.428 revs per second. Times 60: 85.7 rpm.
So holding 24 mph in 50x14 means spinning about 86 rpm, a comfortable endurance cadence. If the group surges to 27 mph, the math gives 96 rpm in the same gear, or shift to the 13 and hold 89. This is why experienced riders shift constantly: they are defending their cadence, not chasing speed, and the calculator shows exactly which gear holds 90 rpm at any speed.
Gear Inches, Explained Simply
Gear inches translate your gearing into the size of an imaginary direct-drive wheel. The formula: chainring teeth divided by cog teeth, times wheel diameter in inches (about 27 for a road wheel). A 50x14 gives 50 divided by 14 times 27, which is 96.4 gear inches. A 34x28 climbing gear gives 34 divided by 28 times 27, which is 32.8 gear inches.
The number tells you how far the bike travels per pedal revolution: gear inches times pi. At 96.4 gear inches, one crank turn moves you 303 inches, or 25.2 feet. At 90 rpm, that is 2,272 feet per minute, which is 25.8 mph. Gear inches let you compare bikes with different wheel sizes directly, and they explain why a mountain bike's 22-inch granny gear feels so different from a road bike's 100-inch top gear: one moves 5.8 feet per turn, the other 26.
Cadence Targets by Rider Type
Flat-road endurance riding sits at 85 to 95 rpm for most trained cyclists. Climbing drops the natural cadence to 70 to 80 as torque rises; forcing 90 uphill usually means the gear is too easy and the heart rate too high. Sprinting lives above 110 rpm, and track sprinters touch 140. Time trialists often ride 95 to 105, trading a slightly higher heart rate for fresher legs off the bike.
Beginners naturally grind at 60 to 70 rpm, which feels powerful but loads the knees. Consciously shifting one gear easier and spinning 10 rpm faster is the cheapest fitness upgrade in cycling: same speed, less joint stress, faster recovery. Check your average cadence after rides, not during; the number to raise over a season is the average, one rpm at a time.
Frequently Asked Questions
What is a good cadence for beginner cyclists?
Most beginners naturally pedal at 60 to 70 RPM and should work toward 80 to 90 RPM. Shifting to an easier gear and spinning faster reduces knee strain and delays leg fatigue. Give it two weeks of conscious practice before judging it.
Is higher cadence always better?
No. Above about 105 RPM most riders bounce in the saddle and waste energy stabilizing themselves. The efficient band for trained cyclists is 85 to 100 RPM on flat ground. Sprinters and track riders go higher, but that is a trained skill.
How can I measure cadence without a sensor?
Count how many times one knee rises in 30 seconds and double it. Do this a few times per ride on flat ground. It is surprisingly accurate and free, though a crank-arm sensor gives continuous data if you want it.
What cadence do professional cyclists ride at?
Pros typically race at 90 to 100 RPM on flat stages and time trials, dropping to 70 to 85 on steep climbs. Lance Armstrong popularized high-cadence climbing in the 2000s, and the peloton largely followed.
Does cadence directly affect my speed?
Yes, mechanically: speed equals cadence times gear development. At fixed gearing, 10 percent more cadence means 10 percent more speed. In practice, your body has an efficient cadence band, and forcing RPM far outside it costs more energy than it gains.
What is a good cadence for climbing hills?
Expect 65 to 80 RPM on real climbs as gears run out and gravity caps speed. If you drop below 60, your lowest gear is too hard for the hill. Seated spinning beats standing and mashing for long climbs.
Should triathletes use a different cadence?
Many triathlon coaches recommend 85 to 95 RPM on the bike leg to spare the running muscles. Mashing big gears at 70 RPM leaves the legs heavy for the run. Practice your target race cadence in training, not just on race day.
How does gear ratio change speed at the same cadence?
Speed scales directly with the chainring-to-cog ratio. Going from a 16-tooth cog to a 15-tooth cog at the same 90 RPM raises speed about 6.7 percent. Try it in the calculator: one shift is worth roughly 1 to 1.5 mph at cruising speeds.
What is the difference between mashing and spinning?
Mashing means pushing big gears at low cadence (under 75 RPM), which loads the knees and fatigues muscles fast. Spinning means easier gears at 85-plus RPM, sharing the work across more strokes. Spinning wins for endurance; mashing has its place in short sprints.
Can cadence drills improve my cycling efficiency?
Yes. Spin-ups (gradually raising RPM to max smooth cadence for 30 seconds), one-leg drills, and high-cadence intervals teach a smoother pedal stroke. Most riders see their natural cadence rise 5 to 10 RPM after a month of drills.