How to Read Tire Size
When you need a new set of tires for your drives around Gulfport, Long Beach, and Biloxi, it’s important to know how to read tire size, so you know you’re making the best choice for your car.
The size of your tires impacts not only safety, but also your driving experience and vehicle longevity, so Pat Peck Honda created this helpful guide.
Where to Find Tire Size
Your vehicle’s ideal tire size is located in one of four places:
- Your owner’s manual
- The driver’s side door jamb
- The glove box door
- The gas tank hatch
You can also look at the sidewall of the tires currently on your vehicle.
For the sake of our example, we looked at the 2018 Honda Accord. For this model, the manual recommends a tire size of P225/50R17 94V.
That may look like a code worthy of a Turing machine, but it’s actually quite simple to decipher. We’ll work through this together in the following sections.
Reading Tire Size: P, LT, T, and ST
The letter at the beginning of your tire size indicates the type of vehicle it’s meant for. P, as in our example, refers to a passenger vehicle like a sedan or SUV. Other letters you may see include:
- LT: Light truck
- T: Temporary
- ST: Special trailer
The first three numbers in this sequence refer to the tire’s width. So, in our example, the proper tires for the 2018 Honda Accord should measure 225 millimeters from sidewall to sidewall.
Tire Size: Aspect Ratio
Next is the height-to-width aspect ratio. Since our example has the number 50 after the slash, that means that the tire’s sidewall height is 50% of the overall tire width.
The higher the ratio, the more donut-shaped the tire becomes. Lower ratios tend to provide improved handling.
This letter will most likely be an R as it is in our example. This means the tire has a radial construction and the internal body piles radiate outward from the center. It’s possible the tire will also have a (D)iagonal construction, meaning the internal body piles crisscross each other diagonally.
How to Read Tire Size: Rim Diameter
The final number that impacts tire size is the rim diameter. In our example it’s a 17. This means that the 2018 Accord needs wheels that fit a rim with a diameter of 17 inches.
Tire Performance Indicators
In addition to information on tire size, the code on your tire’s sidewall also includes two indicators of their performance capacities.
The first is load carrying capacity. This number can range from 0-279 and needs to be cross-referenced with the tire manufacturer’s index. Our example was looking at a set of Hankook tires recommended by our tire center. These have a load index of 94, which means that they can bear a load of 1,477 pounds.
The second piece of information is the speed rating. This is a lettering system that also needs to be cross-referenced with the manufacturer’s site. In our example, a speed rating of V means the tires can tolerate a max speed of 149 MPH.
Buy Your New Tires Today
We love giving our Biloxi area customers car maintenance tips, like how to read tire sizes.
If you’re due for a new set, we welcome you to browse our tire center at Pat Peck Honda near Gulfport and Long Beach. We’ll even install them for you at our on-site service center.
Use our online portal to quickly and easily schedule your service today!