How To Determine Your Wheel Size
We hope you will find this helpful when determining your wheel size.
The most important thing about determining your rim size is actually to NOT measure your wheel.
*Measuring your rim will give you a little over an inch of error.
The rim diameter can be found by simply looking at the sidewall of the tire and locating the series of numbers and letter. The diameter is indicated by an R##.
For additional wheel information you may need to remove the wheel completely from the vehicle.
Keep in mind that although most wheel styles only come in one diameter, vehicles like BMW may have multiple width and offset options for a single wheel style.
Standard steel wheels may actually have their size information on the front of the wheel, check near the outer edge or the center near the lug nuts for part numbers and wheel sizes.