How to Read Tire Sidewall Markings

Start with the information that belongs to your vehicle

A tire sidewall is a compact label, not just a strip of rubber. It identifies the tire’s size and construction and may also show its load capacity, speed category, age, traction information, and intended conditions. Learning to read it makes comparison shopping less mysterious and helps you have a clearer conversation when it is time to replace tires.

Before focusing on the sidewall, find the vehicle tire-and-loading placard. It is commonly located on the driver’s door jamb, though the owner’s manual can confirm the location. The placard lists the manufacturer’s specified tire size and recommended cold inflation pressure for that vehicle. It is a better starting point than copying whatever happens to be mounted on the car, because a previous owner may have changed tire size or type.

Sidewall markings describe the tire; they do not by themselves confirm that it is the correct choice for every vehicle or driving situation. Keep the placard and owner’s manual in view when comparing markings. If something differs from the vehicle information, avoid assuming it is interchangeable simply because it fits on the wheel.

Break down the size code

A common passenger-tire size looks like P215/60R16 95H. The exact letters and numbers vary, but reading the code one piece at a time is straightforward. The first letter, when present, describes a tire classification. P is commonly used for passenger tires. Other prefixes can indicate a different classification, including some light-truck applications. A size with no prefix can use a metric format. The vehicle placard is the reference for the specification intended for your vehicle.

The first three-digit number is the section width in millimeters: 215 in this example. It is a nominal width, not a promise that every tire with that number will measure identically once mounted. The number after the slash is the aspect ratio. A 60 aspect ratio means the sidewall height is roughly 60 percent of the tire’s section width. Lower-profile tires have a smaller aspect-ratio number and a shorter sidewall relative to their width.

The R usually means radial construction, which is common on modern passenger vehicles. The number after it, 16, is the wheel diameter in inches that the tire is designed to fit. A 16-inch tire must be matched with a 16-inch wheel; the other size numbers also matter because they affect the tire’s overall dimensions and operating characteristics.

Why small size changes are not automatically small changes

A wider tire, a different aspect ratio, or a different wheel diameter can change the outside diameter and circumference. That can affect speedometer and odometer readings, clearance, steering feel, and the way vehicle systems interpret wheel speed. Load capacity can change as well. For that reason, it is wise to use the manufacturer-specified size unless a knowledgeable professional has confirmed a suitable alternative for the particular vehicle and wheels.

Understand the load index and speed symbol

In 95H, the number is the load index and the letter is the speed symbol. The load index is a coded value that corresponds to the maximum load a single tire can carry under specified conditions. It is not a pressure recommendation, and it does not tell you how much cargo to put in the vehicle. To compare load capacity, use a reliable load-index chart and make sure the replacement tire meets the vehicle manufacturer’s requirements.

The speed symbol is a category associated with the tire’s tested capability under standardized conditions. It is not a suggestion to drive at that speed, and it does not override legal limits, road conditions, vehicle condition, or safe driving judgment. The symbol also relates to how the tire is designed to manage heat and performance characteristics. Follow the owner’s manual and placard guidance rather than choosing solely by a letter that appears higher or lower in an online listing.

For many vehicles, all tires should have compatible size, construction, load capability, and speed category. Mixing significantly different tires can affect handling and the operation of all-wheel-drive or four-wheel-drive systems. If one tire is damaged and the others are partly worn, ask for vehicle-specific guidance before replacing only one.

Find the manufacturing date code

The Department of Transportation, or DOT, marking identifies a tire that meets applicable U.S. standards and includes a tire identification number. The last four digits of the full code show the week and year of manufacture. For example, 2325 means the tire was made in the 23rd week of 2025. On some tires, the complete code is molded on only one sidewall, so you may need to look at the inward-facing side.

The date code is useful context, especially when inspecting a spare, a lightly used vehicle, or tires that appear to have substantial tread left. Age is not the only measure of tire condition. Storage, exposure, use, inflation history, damage, and vehicle condition all matter. Follow the vehicle and tire manufacturers’ guidance on inspection and replacement, and seek a professional inspection if you see cracking, bulges, cuts, exposed cord, or an unexplained loss of pressure.

Know the markings related to weather and traction

M+S, sometimes written as M&S, is a mud-and-snow designation used on many all-season and some all-terrain tires. It does not mean every M+S tire provides the same level of winter traction. The three-peak mountain snowflake symbol identifies tires that meet a defined snow-traction performance requirement. Neither marking eliminates the need to adjust driving for rain, ice, visibility, road surface, and available traction.

You may also see the Uniform Tire Quality Grading, or UTQG, information on many passenger tires: treadwear, traction, and temperature grades. These grades can help compare tires within their intended category, but they are not a universal scorecard. A treadwear number is a comparative test rating, not a guaranteed mileage figure. The traction grade concerns wet straight-line braking in a specified test, not cornering or winter performance. Temperature grades concern the tire’s resistance to heat under controlled conditions. Read the markings as one set of comparison details, not as a substitute for the right size and application.

Other useful labels

Some sidewalls identify the tire as tubeless, show maximum load and maximum inflation pressure, or note features such as run-flat construction. The maximum pressure printed on the tire is not the routine pressure target for your vehicle. Use the cold pressure on the vehicle placard unless the owner’s manual provides a specific exception. Check pressure when tires are cold with a dependable gauge, and do not reduce or raise it based only on what is molded into the sidewall.

Inspect the tire, not only the label

Sidewall information is important, but a tire also needs regular visual attention. Look for cuts, cracking, bulges, objects embedded in the tread, uneven wear, and damage around the bead area. Check tread depth in several locations across each tire. Wear that is heavier on one edge, in the center, or in patches can signal an issue with inflation, alignment, suspension components, balance, or another condition that deserves attention.

Do not ignore a vibration, pull, repeated pressure loss, or new noise because the sidewall code looks correct. Those symptoms require diagnosis rather than a guess from a label. Master Auto Service publishes wheel alignment, automotive repair, and scheduled maintenance among its services. Drivers in Walla Walla can contact the shop to discuss a tire-related vehicle concern or current service availability.

Use a simple replacement-tire checklist

When you are ready to compare replacement tires, take a photo of the vehicle placard and the complete sidewall marking on each current tire. Note the tire size, load index, speed symbol, and whether the vehicle has all-wheel drive or other manufacturer-specific requirements. Compare the options against the placard and owner’s manual, then ask questions about any difference before authorizing a purchase or installation.

Also keep the spare in mind. Its size, inflation instructions, and speed or distance limits may differ from the road tires. A compact temporary spare is intended for limited use; its sidewall and the owner’s manual provide the relevant restrictions. Checking it periodically avoids discovering a low or unsuitable spare only after a roadside problem.

Frequently asked questions

What does 215/60R16 mean on a tire?

It identifies a tire with a nominal 215-millimeter section width, a sidewall height that is roughly 60 percent of that width, radial construction, and fitment for a 16-inch wheel. It does not independently confirm that the tire is right for a specific vehicle.

Is the maximum PSI on the tire the pressure I should use?

No. The sidewall maximum is not the normal inflation recommendation. Use the cold tire pressure on the vehicle’s tire-and-loading placard or in the owner’s manual.

How can I tell how old a tire is?

Read the last four digits of the DOT tire identification number. The first two digits are the production week and the last two are the year. For example, 2325 indicates the 23rd week of 2025.

Can I replace just one tire?

It depends on the vehicle, the remaining tires’ condition, and the manufacturer’s requirements. Differences in size or tread depth can matter, particularly on some all-wheel-drive and four-wheel-drive vehicles. Get vehicle-specific guidance before replacing only one.