Every tire's size is printed in two places: on the tire itself and on a sticker in the driver's door jamb. Here's how to read it.
Take 225/65R17: 225 is the tire's width in millimeters. 65 is the aspect ratio — sidewall height as a percentage of width. R means radial construction, and 17 is the wheel diameter in inches. You'll also see a load index and speed rating (like 102H) — match or exceed what your vehicle came with.
If the tires on your car aren't the originals, the sidewall might show the wrong size for your vehicle. The door-jamb sticker lists what the manufacturer intended, including correct pressures — trust it first.
All-season tires handle most of the year, but tread depth is what gets you through slush and lake-effect snow — see our tread depth guide. If you drive a lot of gravel or pothole-heavy roads, a slightly taller sidewall (higher aspect ratio) rides better and protects the wheel.
Skip the decoding entirely: our tire finder matches you to your closest shop and pulls live pricing for your exact vehicle — enter your ZIP, pick your car, see real prices. Installation, balancing, and disposal get quoted upfront when you book.
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