To read a tire, look at the writing on the sidewall (for example: P215/65R15 95H) and decode it section by section. This tells you size, type, load, speed rating, and more.

Quick Scoop

  • The code on a tire’s sidewall is like its ID card.
  • Once you know what each block of letters and numbers means, choosing or replacing tires becomes much easier.
  • As of the mid‑2020s, car makers and tire brands still use the same basic format worldwide for passenger vehicles.

Step 1: Find the Main Size Code

Most common format looks like this:

P215/65R15 95H
or
215/55R17 91V

Here’s what each part means:

  • P (or no letter, or LT)
    • P = Passenger vehicle tire (cars, crossovers, many SUVs).
* `LT` = **Light truck** tire for heavier loads (pickups, heavy SUVs).

* No letter = often a European metric passenger tire.
  • 215
    • Tire width in millimeters, measured from sidewall to sidewall.
  • 65
    • Aspect ratio : the sidewall height as a percentage of the width.
    • Here, the sidewall height is 65% of 215 mm.
  • R
    • Construction type.
    • R = radial tire, which is what almost all modern car tires are.
* Radials have flexible sidewalls and a stiff tread area for better wear and fuel economy.
  • 15
    • Wheel (rim) diameter in inches.
    • Your wheel must match this number; a 15‑inch tire fits only a 15‑inch rim.

Step 2: Read Load Index and Speed Rating

After the size, you’ll usually see something like 95H, 91V, 103T, etc.

  • 95 (load index)
    • A code for how much weight one tire can safely carry when properly inflated.
* The actual weight (in kg or lbs) comes from a load index chart.
* You generally should **not go lower** than the load index specified by your vehicle; equal or higher is acceptable.
  • H (speed rating)
    • A letter indicating the maximum sustained speed the tire is rated for under ideal conditions.
* Common ratings on everyday cars:
  * `T` ≈ typical family cars
  * `H`, `V`, `W`, `Y` = higher performance / higher speed tolerance
* You normally should not choose a tire with a **lower** speed rating than what the manufacturer recommends.

Step 3: Look for Extra Markings

Beyond size and speed, tires carry several additional codes and symbols.

Usage and conditions

  • M+S or M&S
    • Mud and Snow : all‑season or winter‑leaning capability.
  • Three‑Peak Mountain Snowflake symbol (a mountain with a snowflake)
    • Indicates the tire meets a defined winter performance standard and is suitable for severe snow.

Brand and model

  • Large lettering with the brand (e.g., Michelin, Goodyear) and tire line (e.g., Pilot Sport, Defender).
  • This helps you match all four tires if you replace only some of them.

DOT and age code

  • A string starting with DOT, followed by letters and numbers.
  • The last four digits show week and year of manufacture :
    • Example: 2623 = 26th week of 2023.
  • Many experts recommend replacing tires around 6–10 years from manufacture, even if tread looks okay, due to aging rubber.

Treadwear, traction, temperature

Often written as:

TREADWEAR 400 TRACTION A TEMPERATURE A

  • Treadwear (e.g., 400)
    • A comparative wear rating within the same brand’s range. Higher usually means longer life, but it’s not an exact mileage promise.
  • Traction (e.g., A, AA, B, C)
    • Wet stopping capability; AA is highest among these codes.
  • Temperature (e.g., A, B, C)
    • Tire’s resistance to heat buildup at speed; A is the highest rating.

Maximum load and pressure

Somewhere near the bead:

  • MAX LOAD 615 kg (1356 lbs)
  • MAX PRESS 300 kPa (44 PSI)

These are maximum limits for the tire itself, not your everyday driving pressure.

  • Use the pressure on the vehicle’s door jamb sticker , not the max number on the tire, for normal inflation.

Step 4: Simple Reading Example

Take: P245/45R20 103W

  • P = passenger tire.
  • 245 = 245 mm wide.
  • 45 = sidewall is 45% of 245 mm.
  • R = radial construction.
  • 20 = fits a 20‑inch wheel.
  • 103 = load index code (supports more weight than, say, a 91).
  • W = high speed rating, performance‑oriented tire.

Step 5: Quick “Checklist” When You Look at Your Tire

When you stand next to your car and look at a sidewall, ask:

  1. What is the type and size?
    • Read the first block: P or LT, width, aspect ratio, R, rim size.
  1. What is the load index and speed rating?
    • Check the two‑ or three‑character code after the size.
  1. Is it all‑season, winter, or performance?
    • Look for M+S, the snowflake symbol, or performance‑oriented speed ratings like V, W, Y.
  1. How old is it?
    • Find the DOT code and read the last four digits for week/year.
  1. What do the safety ratings say?
    • Check treadwear, traction, temperature grades.
  1. What is the max load/pressure?
    • Read the max load and pressure, but remember to use the car’s door‑sticker pressure for daily use.

Mini “Story” Example

Imagine you’re buying two new tires for the front of a compact SUV and your current tires say:

P225/60R17 99H M+S

You walk into a tire shop and see options like:

  • P225/60R17 99H all‑season
  • 225/60R17 99V performance
  • 225/60R17 103T light‑truck‑style tire

Because you read the sidewall:

  • You know you must keep 225/60R17 to match your wheels and clearances.
  • You match or exceed the 99 load index and H speed rating.
  • You choose between all‑season vs more performance‑oriented, knowing how speed ratings differ.

Simple HTML Table: Main Sidewall Elements

html

<table>
  <thead>
    <tr>
      <th>Marking</th>
      <th>What it means</th>
      <th>Example</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>P / LT</td>
      <td>Tire type (passenger or light truck)</td>
      <td>P215/65R15</td>
    </tr>
    <tr>
      <td>215</td>
      <td>Width in millimeters</td>
      <td>215 mm wide</td>
    </tr>
    <tr>
      <td>65</td>
      <td>Aspect ratio (sidewall % of width)</td>
      <td>65% of 215 mm</td>
    </tr>
    <tr>
      <td>R</td>
      <td>Radial construction</td>
      <td>R = radial</td>
    </tr>
    <tr>
      <td>15</td>
      <td>Wheel diameter in inches</td>
      <td>Fits 15&quot; rim</td>
    </tr>
    <tr>
      <td>95</td>
      <td>Load index code</td>
      <td>95H (load + speed)</td>
    </tr>
    <tr>
      <td>H</td>
      <td>Speed rating letter</td>
      <td>H, V, W, etc.</td>
    </tr>
    <tr>
      <td>M+S / Snowflake</td>
      <td>All-season or severe-snow rating</td>
      <td>M+S, 3PMSF symbol</td>
    </tr>
    <tr>
      <td>DOT XXXX 2623</td>
      <td>Manufacture code; week 26 of 2023</td>
      <td>Age of tire</td>
    </tr>
    <tr>
      <td>TREADWEAR / TRACTION / TEMPERATURE</td>
      <td>Wear and performance grades</td>
      <td>TREADWEAR 400, TRACTION A, TEMP A</td>
    </tr>
  </tbody>
</table>

Quick TL;DR

  • Read the first block for size and type (P215/65R15).
  • Read the second block for load and speed (95H).
  • Scan for M+S / snowflake , DOT date , and treadwear/traction/temperature for use case, age, and performance.

Information gathered from public forums or data available on the internet and portrayed here.