Calculation of tire diameter
1. The relevant parameters are written on the side of your tire.
2. Tire diameter=2×L(total tire width)×V(flatness)/100+d(wheel diameter)×25.4
Example:Suppose your tire parameters are 205/65R16, where L=205mm, V=65, d=16 inches.
Then the tire diameter is 2×205×65/100+16×25.4=679.2mm=67.92cm