Rear End Ratio Calculator


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Fill in three of the 4 values, then click the corresponding "Compute" button. Don't enter letters. Experiment with it. You can find out some useful information (how will changing tire size affect your speedometer reading?)


Enter: Engine RPM, Tire Diameter and Speed


Enter: Engine RPM, Tire Diameter and Gear Ratio


Enter: Tire Diameter, Speed and Gear Ratio


Enter: RPM, Speed and Gear Ratio
Enter the Engine RPM
Enter the Tire Diameter (inches)
Enter the Speed (Miles per Hour)
Enter the Gear Ratio - 3.0 for 3.0:1