Tire Size Calculator

Use the following calculators to find the dimensions of a tire from its code or to compare two different tire sizes.

Find Tire Dimensions

Tire Size: / R
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Tire Size Comparison

Tire 1: / R
Tire 2: / R

Understanding the Tire Code

Car tires are described by an alphanumeric code (e.g., P265/70R17). Each part of the code specifies a key characteristic of the tire.

  • P - The first letter indicates the vehicle type (P for Passenger, LT for Light Truck).
  • 265 - The "Section Width" in millimeters, measured from sidewall to sidewall.
  • 70 - The "Aspect Ratio," which is the height of the sidewall as a percentage of the width. In this case, the sidewall is 70% of 265mm.
  • R - The internal construction type (R for Radial).
  • 17 - The "Wheel Diameter" in inches that the tire is designed to fit.