Where do I find my gear ratios?

In the gearbox specification for your exact engine/gearbox code, often in the workshop manual or on enthusiast forums.

Gear Ratio & RPM to Speed Calculator

Enter gearbox and final drive ratios with the tire size to find the speed at any RPM.

Results

Updates as you type. Nothing you enter leaves your browser.

Formula

Speed = RPM ÷ (gear ratio × final drive) × tire circumference × 60. Tire circumference comes from the tire size. Real speeds differ slightly because tires flatten under load.

FAQ

Where do I find my gear ratios?: In the gearbox specification for your exact engine/gearbox code, often in the workshop manual or on enthusiast forums.

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