Reading a tire sidewall may seem tricky, but when you know the basics, it’s easy. You’ll see a few words you recognize, like the tire make and model. The most essential tire information on the sidewall for you to understand is the tire size, speed, and load ratings, which look something like 205/55R16 91V.
205 is the tire’s width in millimeters,
55 is the aspect ratio (the height of the tire’s sidewall as a percentage of its width),
R stands for Radial (the tire’s construction)
16 is the diameter of the wheel in inches
91 is the load index (the weight the tire can carry)
V is the speed rating (the maximum speed you should use the tire at)
You’ll also find a Tire Identification Number, which starts with DOT and tells you when and where the tire was made. Other markings like M+S indicate the tire’s suitability for driving in mud and snow.