We’ll get to what those other numbers on your tires mean a little later, but you can always check your existing tires to see what size you need. There are three important numbers to remember when buying tires. The simple terms for these numbers are Width, Aspect Ratio, and Diameter. For example, if the side of your tire says, “225/50/17”, it means your tire is 225 millimeters wide, the sidewall of your tire is fifty percent as tall as your tire is wide (112.5 cm in this case), and the inner diameter of the tire is 17”. That means that if you’re shopping on our site, you’d be looking for tires sized at 225/50/17.
Remember though, TireTutor will always give you the manufacturer’s recommended size for your car.