Speed from Cadence & Gearing
Calculate speed from cadence and gear ratio. Most cyclists perform best at 80–100 RPM. Pros like Chris Froome average ~97 RPM. Gear ratio = chainring ÷ cog.
Why This Stat Matters
Why: Cadence and gearing determine speed. Optimal cadence is 80–100 RPM for most riders. Sprinters hit 110–130 RPM. Lower cadence stresses muscles; higher stresses cardiovascular system.
How: Speed (km/h) = Cadence × Gear Ratio × Wheel Circumference × 60 ÷ 1,000,000. Enter cadence, chainring, cog, and wheel size. Development = distance per crank revolution.
- ●80–100 RPM optimal for most; pros ~97 RPM
- ●52/11 = 4.73 ratio; 34/28 = 1.21 climbing gear
- ●Sprinters hit 110–130 RPM in 52/11
Speed = Cadence × Gear Ratio × Wheel Circumference × 60 / 1,000,000
Sheldon Brown • CyclingTips • BikeCalc
Preset Scenarios
Screenshot Summary
At 90 RPM in 50/15 on 700c: 23.4 mph (37.7 km/h). Development 6.99 m/rev, 90 gear inches.
Gear Table at 90 RPM
| Chain/Cog | Ratio | km/h |
|---|---|---|
| 53/11 | 4.82 | 54.5 |
| 52/11 | 4.73 | 53.5 |
| 50/11 | 4.55 | 51.4 |
| 53/12 | 4.42 | 50.0 |
| 52/12 | 4.33 | 49.0 |
| 50/12 | 4.17 | 47.2 |
| 53/13 | 4.08 | 46.1 |
| 52/13 | 4.00 | 45.3 |
| 50/13 | 3.85 | 43.5 |
| 39/11 | 3.55 | 40.1 |
| 53/15 | 3.53 | 40.0 |
| 52/15 | 3.47 | 39.2 |
| 50/15 | 3.33 | 37.7 |
| 39/12 | 3.25 | 36.8 |
| 53/17 | 3.12 | 35.3 |
| 34/11 | 3.09 | 35.0 |
| 52/17 | 3.06 | 34.6 |
| 39/13 | 3.00 | 34.0 |
| 50/17 | 2.94 | 33.3 |
| 34/12 | 2.83 | 32.1 |
Quick Reference
At 90 RPM on 700c: 50/15 ≈ 37.7 km/h | 52/11 ≈ 54.5 km/h | 34/28 ≈ 20.2 km/h. Use the gear table above for your exact setup.
Formula: Speed (km/h) = Cadence × (Chainring ÷ Cog) × Wheel Circumference (m) × 60 ÷ 1000
For educational and informational purposes only. Verify with a qualified professional.
🏅 Sports Records
Most cyclists perform best at 80–100 RPM. Pros like Chris Froome average ~97 RPM
Gear Ratio = Chainring ÷ Cog. 52/11 = 4.73; 34/28 = 1.21
Sprinters hit 110–130 RPM in 52/11 or 53/12
Speed (km/h) = Cadence × Gear Ratio × Wheel Circumference (mm) × 60 ÷ 1,000,000. Gear Ratio = Chainring ÷ Cog. Optimal cadence: 80–100 RPM. Chris Froome averages ~97 RPM.
Key Takeaways
- 80–100 RPM is the optimal cadence range for most cyclists
- Gear ratio affects speed linearly: bigger chainring or smaller cog = faster
- 700c wheel circumference ≈ 2096 mm (2.096 m) with standard tire
- Development = Gear Ratio × Wheel Circumference (distance per crank rev)
Did You Know?
How It Works
Step 1: Gear Ratio = Chainring teeth ÷ Cog teeth. Example: 50÷15 = 3.33
Step 2: Development = Ratio × Wheel Circumference (m). Example: 3.33 × 2.096 ≈ 6.98 m/rev
Step 3: Speed (km/h) = Cadence × Development × 60 ÷ 1000. At 90 RPM: 90 × 6.98 × 0.06 ≈ 37.7 km/h
Expert Tips
Cadence Comparison
| Scenario | Cadence | Result | Verdict |
|---|---|---|---|
| Recovery | 60–70 RPM | Low muscle load | ✅ Easy |
| Optimal | 80–100 RPM | Best efficiency | ✅ Recommended |
| High spin | 100–120 RPM | Cardio stress | ⚠️ Use sparingly |
| Sprint | 120+ RPM | Coordination limit | ❌ Efficiency drops |
Infographic Stats
Official Sources
Disclaimer: Speed estimates assume no slip, constant cadence, and standard tire pressure. Actual speed varies with wind, gradient, and rolling resistance.