Gear Ratio Speed Calculator
Calculate vehicle speed from engine RPM, gear ratios, final drive ratio and tire size, with mph and km/h results.
Calculate speed by gear ratio
Gear-ratio speed searches expect a drivetrain calculator: engine RPM, gear ratio, final drive and tire circumference determine wheel RPM and road speed.
Frequently Asked Questions
Sources and References
Calculations are based on the listed reference sources. Links open in a new tab.
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