Calculate and compare every gear combination in your drivetrain. See gear ratios, gear inches, development, and speed at any cadence for road, gravel, and mountain bike setups.
A gear ratio describes the mechanical advantage of your drivetrain. It is calculated by dividing the number of teeth on your chainring by the number of teeth on the rear cog. A higher ratio means more distance per pedal stroke but requires more effort, while a lower ratio is easier to pedal and ideal for climbing.
Modern drivetrains offer a wide range of gear ratios through cassettes with 10 to 13 sprockets. Whether you ride a 1x mountain bike setup or a 2x road groupset, understanding your available gear ratios helps you choose the right gearing for your terrain and fitness level.
Chainring teeth ÷ cog teeth. A ratio of 3.0 means the rear wheel rotates 3 times per pedal revolution. Higher ratios = more speed, lower ratios = easier pedaling.
Gear ratio × wheel diameter (in inches). This traditional metric lets you compare gearing across different wheel sizes. Typical road gears range from 20" to 120".
The distance traveled per pedal revolution. Calculated as gear ratio × wheel circumference. An intuitive metric that tells you exactly how far each pedal stroke takes you.
Your speed in km/h at a given pedaling cadence (RPM). Most efficient cyclists pedal at 80–100 RPM. Use this to find which gear gets you to your target speed.
Your ideal gearing depends on the terrain you ride, your fitness level, and your preferred cadence. For flat terrain and racing, prioritize high gears with a top ratio above 4.0. For hilly routes, ensure your easiest gear has a ratio at or below 1.0 to keep your cadence comfortable on steep climbs.
If you frequently ride varied terrain, look for a drivetrain with at least a 400% gear range. Modern 12-speed cassettes from Shimano and SRAM easily achieve this. Use the calculator above to compare presets and find the setup that matches your riding style.
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Enter each cog's tooth count separated by commas
Select a groupset preset or enter custom chainring and cassette values to see all gear combinations