This calculator requires the use of Javascript enabled and capable browsers. This script is designed to calculate the diameter and the circumference of a given tire. Both calculations are designed to round up. Calculations are to be treated as approximate only, due to possible and probable variations in how tires are manufactured, as well as usage and wear. The information in the Required area is needed to perform the comparison. The following is an example to help to decode a tire size like 255/60R17. The 255 is the tire width in millimeters, measured from the bottom of the bead to the bottom of the bead, the 60 is the sidewall aspect ratio (the tire width factor), the ratio of sidewall height to tire width at the tread (indicating that the sidewall height is 70% of the tread width), and the 17 is the wheel rim diameter in inches. After the data entry of the required information, click on Calculate to obtain the resulting values. For more calculations, take a look at our U.S And Metric Tire Size Information Calculator.
