Car Tire Specifications

When you buy new car tires, you’ll either go online and enter your car’s year, make, model, and trim or give that information to someone at a store. Unfortunately, the tire specifications you get in response will not necessarily be correct. For the past 13 years, I’ve been buying car tires for my 2003 Honda Accord DX and the tire specs I’d be given are

This information was taken from and from the tire specialist’s computer at a Costco Tire Center. It says that my tire size is P215/60R17. The tire specs in the driver side door, however, says this:

It says that my tire size should be P205/65R15. While it may be okay to go with a slightly different size, it’s probably better to go with the manufacturer’s recommendation.

Here’s an explanation of a tire’s size using P215/65R15 95H as an example.

Tire Type

P = P-metric tire made to US standards for passenger vehicles

Tire Width

215 = tire width in millimeters from sidewall to sidewall

Ratio of Height to Width

65 means the height of the tire is 65% of its width. The bigger the aspect ratio, the bigger the tire’s sidewall will be.


R stands for Radial, which means the layers run radially across the tire.

Wheel Diameter

15 means the tire is made for a wheel with a 15 inch diameter

Load Index

95 indicates the tires can carry a load of 1,521 lbs. The higher the number, the higher the load carrying capacity. You can find load index tables online.

Speed Rating

H = symbol to specify tire’s maximum speed. H corresponds to a max speed of 130 mph. Tire speed rating charts are available online.

Based on the information above, if I had purchased tires based on what Costco’s website told me, i.e. P215/60R17, instead of P205/65R15, then the diameter of the tire’s opening for the wheel would be 2 inches too large for my factory wheels and therefore not fit.