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Tire Size Comparison Calculator
Enter two tire sizes (width/aspect ratio/rim diameter) to compare their overall diameter and estimated speedometer difference.
How to use this tool
- 1Enter your original tire's width, aspect ratio, and rim size.
- 2Enter the new tire's specs.
- 3See the diameter and speedometer difference.
Frequently asked questions
How much difference is safe?+
Most tire shops recommend staying within about ±3% of the original diameter to avoid speedometer error and fitment issues.
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