Bike Gear & Speed Calculator
Instantly calculate gear ratio, gear inches, meters development, and estimated speed based on your drivetrain setup and pedalling cadence.
Calculate Your Bike Gearing
Enter your bicycle’s wheel size, chainring, cog, and typical cadence below to get instant, precise gearing and speed metrics.
Drivetrain Details
Enter your bike’s specifications to calculate metrics
Gearing Results
Calculated based on standard cycling formulas
Common Gear Setups
Typical gear combinations and their resulting metrics on a standard 700c road bike for quick comparison.
| Setup (Chainring/Cog) | Gear Ratio | Gear Inches | Meters Dev. |
|---|---|---|---|
| 34 / 34 (Climbing) | 1.00 | 27.0″ | 2.10 m |
| 34 / 28 (Easy Spin) | 1.21 | 32.8″ | 2.55 m |
| 50 / 25 (Moderate) | 2.00 | 54.0″ | 4.20 m |
| 50 / 17 (Cruising) | 2.94 | 79.4″ | 6.18 m |
| 50 / 15 (Fast) | 3.33 | 90.0″ | 7.00 m |
| 53 / 11 (Sprint/TT) | 4.82 | 130.0″ | 10.12 m |
Bike Calculator FAQ
Everything you need to know about bicycle gearing, cadence, and how to optimise your drivetrain.
Gear inches is a traditional measurement of bicycle gearing. It represents the diameter of the drive wheel of a penny-farthing bicycle that would travel the same distance per pedal revolution. A higher gear inch number means a ‘harder’ gear that covers more distance per pedal stroke but requires more force.
Meters development (or rollout) is the metric equivalent of gear inches. It measures the exact distance in meters the bicycle travels forward for one complete revolution of the pedals. It is calculated by multiplying the gear ratio by the wheel’s circumference in meters.
For most recreational and fitness cyclists, a cadence of 80 to 100 revolutions per minute (RPM) is considered optimal. Professional road cyclists often maintain 90-110 RPM, while mountain bikers might drop to 70-90 RPM depending on the terrain. A higher cadence reduces muscular fatigue and shifts the workload to the cardiovascular system.
Larger wheels have a greater circumference, meaning they cover more distance per revolution. For the same gear ratio and cadence, a bike with 29-inch wheels will travel faster and have a higher gear inch measurement than a bike with 26-inch wheels, though it may require more initial effort to accelerate.