Tyre Size Calculators
This page contains all the tyre size calculators and converters that are spread amongst the Wheel & Tyre, all presented on a single page for quick reference.
The DOT Age Code Calculator:
This converter will turn your imperial tyre size into a metric tyre size:
Your imperial tyre size: X
Equivalent standard tyre size is : /100 R
Converting LT (Light Truck) imperial tyre sizes to metric:
Your LT tyre size: X R
Equivalent standard tyre size is : / R
Converting alpha numeric vintage tyre sizes to metric:
This calculator will convert alpha numeric vintage tyre sizes into the closest metric tyre size. Remember the section width is only a close approximations between old load and new size these days:
C = 185 D = 195 E = 205 F = 215 G = 225 H = 235 etc.
Your alphanumeric tyre size: R
Equivalent standard tyre size is: / R
Converting Michelin PAX tyre sizes to metric:
This calculator will convert Michelin PAX sizes into the closest metric tyre size.
Your PAX tyre size: / R
Standard tyre size is: / R
Comparing tyre sizes:
This calculator will help you to compare two different tyre sizes to see the differences in rolling circumference, and any speedometer difference error between the two sizes.
Current wheel/tyre | New wheel/tyre |
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/ R | / R |
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Current rolling circumference mm |
New rolling circumference mm |
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Difference in circumference:mm or% | |
So when your speedo reads 70mph, you're actually travelling atmph |
Comparing wheel offsets:
This calculator will help you to understand how changing your wheel offset will affect the wheel's position in relation to your suspension and bodywork.
Current wheel/tyre | New wheel/tyre |
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Tyre Section: Wheel offset: | Tyre Section: Wheel offset: |
Calculating ideal rim width for any given tyre size:
This calculator will give you the ideal wheel rim size for any given tyre size.
Your tyre size: / R
Rim size is: X up to X