What Do the Numbers on Tires Mean?

Cars have lots of technologies today. From indicator lights that mean it’s time to service your vehicle to alert noises and lights that mean there’s someone in your blind spot and more, there’s a whole lot to decipher in the automotive space nowadays. But a more straightforward message that needs decoding relates to tire number meaning. Precisely what do the numbers on your tires mean? Learn all about tire number meaning & significance now with the Ryan Chrysler Jeep Dodge service center. Don’t hesitate to contact us with any additional questions as they crop up!

Deciphering Tire Number Meanings

Tire numbers are essentially a code made up of a series of letters and numbers in a particular order. Put together, they tell you things that are important to know about your tire, including its:

• Size 
• Load index
• Speed rating
• Type of tire (construction)

Take this code, for example, to learn more about tire number meaning.

Example: P215/65R15 95H

While it may seem like gibberish, each code of code represents a piece of information to identify the type of tire correctly.

• Decoding “P”: The “P” means “P-Metric tire,” which means that this tire is used for passenger vehicles only. (If your tires read “LT,” this stands for “light truck,” and the tire is intended for light-weight pickup trucks). If the tire does not have a letter preceding the code, it is a European-style tire, otherwise known as a Euro-Metric tire.
• Decoding “215”: Following the “P” is the number “215”, which tells you your tire’s width in millimeters from sidewall to sidewall.
• Decoding “65”: After the slash, you’ll see the aspect ratio code, signified in this example by “65.” A tire’s ratio is the height of the tire’s cross-section to its width, so in this example, the tire in question has an aspect ratio where its height is equal to 65% of its width. Larger aspect ratios correlate with larger sidewalls. Lower aspect ratios correlate with thinner or lower-profile sidewalls.
• Decoding “R”: The “R” indicates the tire’s construction, with “R” denoting that it’s a radial tire.
• Decoding “15”: “15” indicates the wheel size from one end to the other. This code tells us that the tire in question is meant to be fitted on a 15-inch-diameter wheel.
• Decoding “95H”: At the end of the code is “95H,” which is the tire’s load index and speed rating. The load index (“95” in this instance) indicates how much weight the tire can support when it’s properly inflated and can range from 75-105 for passenger vehicles. “H” represents the speed rating, which is how fast the tire can safely go based on its load capacity. This rating is ranked from A-Z, and with our example, a tire with an “H” rating can reach a maximum speed of 130 mph.

How to Check Tire Pressure Yourself

No matter which size tires your car rides on, you’ll want to make sure you keep them properly inflated. To do that, it’s helpful to learn how to conduct a DIY tire pressure test! 

Checking your tire pressure is easy. Today, most cars come with a standard Tire Pressure Monitoring System (TPMS) that may even give you a digital reading of each tire’s PSI. If your vehicle’s tires are overinflated or underinflated, you’ll receive a notification from the TPMS system. You also, however, can use a pressure gauge to read how much your tires are inflated. Many gas stations or convenience stores now offer vacuum and tire air combination machines that give you an accurate reading of your tire pressure as well for a small price.

Turn to Ryan Chrysler Jeep Dodge for All Your Maintenance Needs.

Now that you know the answer to the question “what do tire numbers mean?” we hope you’ll rely on us here at the Ryan Chrysler Jeep Dodge service center with all your service and maintenance needs! Looking to have our experts evaluate your tire health? Schedule service now!