Your tire size is printed on the sidewall of every tire and in your owner's manual

The fastest way to find your tire size is to look at the sidewall of any tire on your vehicle. Walk around to one of your wheels and read the markings stamped into the rubber on the side of the tire facing outward. The tire size appears as a string of numbers and letters — something like 225/65R17 or P195/60R15 — and it is the same on all four tires (unless you have mismatched tires, which is uncommon).

If you cannot access your tires easily or prefer not to bend down to read them, your vehicle's owner's manual lists the correct tire size in the specifications section. You can also find it on a sticker inside your driver's side door jamb, on the fuel door, or in the glove compartment. Some vehicles have the size printed on the spare tire as well.

Key Takeaways

  • Your tire size is stamped on the sidewall of each tire in a format like 225/65R17, and you can read it directly without tools.
  • Your owner's manual, the driver's side door jamb sticker, and your vehicle's fuel door all display the correct tire size.
  • The tire size tells you the width, aspect ratio, construction type, and wheel diameter you need when replacing tires.
  • If you lose the manual or cannot find the sticker, a tire shop or dealership can look up your size using your vehicle's year, make, and model.

Reading the sidewall markings

The tire size code breaks down into four parts. The first number (like 225) is the tire width in millimeters. The second number after the slash (like 65) is the aspect ratio — the height of the tire sidewall as a percentage of the width. The letter (R) indicates radial construction, which is standard on all modern tires. The final number (like 17) is the wheel diameter in inches.

You may also see a letter at the very beginning of the code, like P225/65R17. The P stands for passenger vehicle, while LT means light truck. This matters because truck tires are built differently and rated for heavier loads. Using the wrong type can affect how your vehicle handles and how long the tires last.

Checking the door jamb sticker

Open your driver's side door and look at the edge of the door frame where it meets the body of the vehicle. You will see a white or silver sticker with vehicle information printed on it. This sticker lists the correct tire size for your vehicle, along with the recommended tire pressure for both front and rear tires.

The door jamb sticker is useful because it shows the manufacturer's recommended size, which may differ from what is currently on your vehicle if the tires were replaced with a different size. If you are replacing tires and want to stay with what the manufacturer intended, this sticker is your reference. The information on this sticker does not change and is specific to your vehicle's year, make, and model.

Using your owner's manual

Your vehicle's owner's manual contains a specifications section that lists tire size, recommended tire pressure, and load capacity. If you still have the physical manual, look in the index under "Tires" or "Specifications." The manual will show the size in the same format you see on the sidewall.

If you no longer have the printed manual, you can find a digital copy online. Search for your vehicle's year, make, and model plus "owner's manual PDF," and you should find free versions on manufacturer websites or automotive resource sites. Once you have the manual open, the tire information is usually in the first few sections.

Getting the size from a tire shop or dealership

If you cannot locate any of these sources, a tire shop or your vehicle's dealership can tell you the correct size in seconds. Call ahead or visit in person with your vehicle's year, make, model, and VIN (vehicle identification number). The VIN is printed on your registration, insurance card, and on a small plate visible through the windshield on the driver's side dashboard.

Tire shops look up this information constantly and can confirm your size without charging you. This is also a good time to ask whether your current tires match the manufacturer's recommendation or whether they differ, which helps you decide whether to replace with the same size or switch back to the original.

Understanding tire size variations

Some vehicles come with multiple tire size options from the factory, depending on which trim level or wheel package you ordered. A base model might come with 215/60R16 tires, while a sport trim comes with 225/65R17. Both are correct for that vehicle — it depends on which one you actually have.

If you replace your tires with a different size than what is currently on your vehicle, the speedometer, fuel economy readings, and handling can all change slightly. Most tire shops will not recommend switching sizes without a specific reason, but it is possible if you want a different wheel diameter or a tire with different performance characteristics. The door jamb sticker shows the manufacturer's preferred size, which is the safest choice for replacement.

What to do with the size once you have it

Once you know your tire size, write it down or take a photo of the sidewall marking. Keep this information in your phone or in your vehicle's glove compartment. When you need new tires, you can give this size to any tire retailer — online, at a shop, or at a warehouse club — and they will show you options that fit your vehicle.

You will also need this size if you ever need to buy a spare tire, have a flat repaired, or check tire pressure. Tire pressure gauges and air pumps at gas stations often have size guides, and knowing your size helps you inflate to the correct pressure listed on your door jamb sticker.

Frequently Asked Questions

Can I use a different tire size than what is on my vehicle now?

You can, but the manufacturer's recommended size (on the door jamb sticker) is designed for your vehicle's weight, suspension, and performance. Switching sizes changes how your speedometer reads and affects fuel economy. A tire shop can tell you which alternative sizes are safe for your vehicle.

What if the sidewall is too worn to read?

Check the door jamb sticker, your owner's manual, or the spare tire. If none of those are available, a tire shop can look up the size using your vehicle's VIN. You can also call your vehicle's dealership with the year, make, and model.

Do all four tires have to be the same size?

Yes, all four tires should match in size and type. Mismatched tires can cause handling problems and may damage your transmission or all-wheel-drive system. If you have a flat and need a temporary replacement, use the spare only until you can replace the damaged tire with the correct size.

Is the tire size the same as the wheel size?

No. The tire size includes the wheel diameter as the last number (like 17 in 225/65R17), but the wheel itself may have different offset or width specifications. When replacing wheels, you need both the tire size and the wheel specifications.