Using the example numbers the tires aspect ratio would calculate as 215x.65=139.75 where 139.75 is the tires height in millimeters. 215) by the second number with a decimal before the number (e.g.65). To calculate the aspect ratio, multiple the first number (e.g. An example of this might be 65, which means that the height is equal to 65% of the tire’s width. An example might be 215 representing 215 millimeters.Īspect Ratio – This is the ratio of the height of the tire’s cross-section to its width. Tire Width – This is the width of the tire measured in millimeters from sidewall to sidewall. P indicates this is a passenger car tire while LT indicates the tire would be for a light truck with a heavier load rating. Tire Type – This Defines the intended proper use of the tire. The following will help you understand what this information means. Some of the information is self explanatory while other information requires a little knowledge to decipher. Rim SizeĪll tires are required to have certain information molded into the side of the tire in a location known as the sidewall. If you need to know the actual p-metric tire size and the equivalent measurements in inches for a specific tire, check with the manufacturer’s actual dimensions per individual tire brand before purchasing. This chart is for an estimated conversion and the actual advertised tire height and tread width will vary from manufacturer to manufacturer.

The values shown are calculated measurements based on the p-metric formula, which is explained below on this page. The following chart lists common p-metric tires sizes and the converted tread width and the actual tire height in inches. Guide to P-Metric Tire Sizes, Conversion Chart and Tire Terminology – P-Metric to Inches

Tire size metric to standard calculator