215/45 R18 tires' overall diameter is 25.6 inches, tire width is 8.5 inches, the tire can be mounted on 18 inches wheel and the circumference is 80.4". With that parameters, we can calculate that it will take approximately 788.1 revolutions per mile.
So the closest metric tire size of 215/45R18 existing size in inches is 33x10.50R18, which is 28.91% taller and 23.53% wider.
For each tire size there often there are several wheel sizes. You can't put too wide tires on narrow rims or vice versa. Here is what size of the wheels your vehicle needs for 215/45 R18 tires:
Rim diameter x rim width
215/45 R18 – what does it mean?
The first number shows that the tire has a section width of 215 mm or approximately 8.5 inches.
The second number is the aspect ratio or sidewall height. In this case, it is 45%. It shows the height of the tire from the ground to the rim edge or the height of the tire's cross-section which
is 45% of the width or ~ 97mm
The letter R means this tire is radial. Most of all tires nowadays are radial. The number is the tire diameter in inches.
It means that the tire will fit 18-inch wheels
If you want to know more about how to decipher information inscribed on your tires, including aspects such as the tire height, tire width, and the diameter of the wheel, this guide provides an in-depth look at how to read a tire sidewall. These measurements can reveal a wealth of information about your tire's specifications and suitability for your vehicle. Mastering these details will allow you to make informed decisions when buying or replacing your tires.