Compare tire sizes in seconds.
Enter the current and proposed tire sizes. VeroRoad calculates overall diameter, circumference and the approximate speedometer difference at 60 mph.
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Why diameter difference matters
A large change can affect speedometer/odometer accuracy, gearing, clearance and some driver-assistance or ABS behavior. Fitment also depends on wheel width, offset, load rating and physical clearance — this calculator covers tire geometry only.
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