The numerous units help tire experts precisely discuss, classify or describe tire and wheel dimensions. You have probably already seen some dimensions in your tire’s sidewall code and want to know how to read it. This tire size code comprises the section width, aspect ratio, and rim diameter.
Section Width
The section width describes the distance between the outer sidewall's widest point and the inner sidewall's widest point. This physical width can change if the tire is mounted on a wheel slightly wider or narrower than the size indicated by the rim width. Section width is the first number in a metric tire size code.
Overall Width
The overall width is the tire's width from sidewall exterior to sidewall exterior, including any features molded onto the sidewall's outside. Overall width pertains mostly to tires with decorative whitewalls on the exterior sidewall, or to off-road tires with rim protectors.
Tread Width
The tread width is the distance between the two outer edges of a tire's tread.
Rim Width
The rim width is the acceptable range of wheel widths approved for a particular size of tire.
Section Height
The section height is the distance between the top of the tire tread and the bottom of the tire bead. This measurement is used to determine the aspect ratio, which helps determine if certain plus sizes can be mounted on a given vehicle.
Overall Diameter
The overall diameter measures the tire's outside diameter through its exact center when inflated and with no load.
Rim Diameter
The distance between the bottom the bead seat area, directly across from each other, on the same side of the wheel. This is used to ensure a matching wheel diameter is compatible with the tire. Rim diameters start at four inches.
Circumference
Circumference measures the 360 degree distance around the outside of the tire tread. This measurement is used to calculate the revolutions per mile.
Do you still have any questions or need help finding your tire size? Stop by or save some time and make an appointment online! We’ll get you taken care of.
Get a shorter wait time in-store when you buy and book online!