The load index is a number on your tire's sidewall that tells you the maximum weight that single tire can safely carry

Every tire has a two or three-digit number stamped into its sidewall — that is the load index. It appears right after the tire size in the format you see on your vehicle's door jamb or owner's manual. A tire marked 95, for example, can carry up to 1,521 pounds when inflated to its rated pressure. A tire marked 120 can carry 3,197 pounds. The number itself is not a weight in pounds; it is a code that corresponds to a specific weight capacity on a standardized chart.

The load index matters because using a tire with an index too low for your vehicle can cause the tire to overheat, wear unevenly, and fail suddenly — especially under highway speeds or when the vehicle is fully loaded. Conversely, a tire with a higher load index than required is safe to use; it straightforward costs more and may affect fuel economy slightly. The key is meeting or exceeding your vehicle's requirement, not guessing at what feels right.

Key Takeaways

  • The load index is a two or three-digit number on your tire's sidewall that corresponds to a maximum weight capacity listed on a standardized chart.
  • Your vehicle's door jamb or owner's manual specifies the minimum load index required; you must meet or exceed that number when replacing tires.
  • Using a tire with a load index lower than required can cause overheating, uneven wear, and sudden failure, especially at highway speeds or with a full load.
  • The load index is always paired with a speed rating (a letter like H, V, or W) that indicates the maximum safe speed for that tire.

Where to find your vehicle's required load index

Your vehicle's door jamb — the frame around the driver's side door — has a sticker listing the tire size and load index your manufacturer recommends. This is the number you must match or exceed when you buy replacement tires. If the sticker is missing or hard to read, your owner's manual contains the same information in the tire specifications section.

Do not rely on the tires currently on your vehicle if you inherited the car or are unsure whether they were the correct choice. The previous owner may have installed tires that do not meet the manufacturer's requirement. Always check the door jamb sticker or manual first, then verify the replacement tire's load index before purchase.

How the load index number is assigned

The load index uses a standardized scale that starts at 0 (99 pounds) and goes up to 150 (7,385 pounds). Each number represents a specific weight capacity. The scale is not linear — the jump from index 90 to 91 is not the same as the jump from 100 to 101. Instead, each step up represents roughly a 3 percent increase in capacity.

Tire manufacturers test each tire design to determine its maximum safe load at its rated pressure. That capacity is then matched to the closest index number on the chart. A tire rated for 1,521 pounds gets a 95; a tire rated for 1,609 pounds gets a 96. The index is printed on the sidewall during manufacturing and does not change over the tire's life, even as the tire wears.

Load index paired with speed rating

The load index always appears alongside a speed rating — a single letter like H, V, W, or Y. The speed rating tells you the maximum speed at which that tire can safely carry its rated load. An H-rated tire, for example, is safe up to 130 mph; a V-rated tire up to 149 mph. Both the load index and speed rating must be appropriate for your vehicle.

A tire with a high load index but a low speed rating (or vice versa) is not a safe choice for highway driving. If your vehicle's door jamb specifies a 95H tire, you need a tire with at least a 95 load index and at least an H speed rating. A 95V or 95W is acceptable; a 94H is not, even though the speed rating matches.

What happens if you use the wrong load index

A tire with a load index lower than required will flex more than it should under the vehicle's weight. This excess flexing generates heat inside the tire, which weakens the rubber and the internal structure. Over time — or suddenly under highway speeds — the tire can separate, blowout, or fail without warning. The risk is highest when the vehicle is fully loaded (passengers, cargo, towing) or when driving long distances at sustained speeds.

A tire with a load index higher than required is safe but unnecessary. It will cost more at purchase and may reduce fuel economy slightly because the stiffer sidewall requires more energy to flex. There is no safety penalty for exceeding the requirement, only a cost and efficiency trade-off. Many drivers choose to match the requirement exactly to balance safety and value.

Load index for trucks and vehicles that tow

Trucks and SUVs that tow or carry heavy loads often have higher load index requirements than sedans of similar size. The door jamb sticker accounts for the vehicle's maximum loaded weight, including passengers, cargo, and tongue weight from a trailer. If you plan to tow or regularly carry heavy loads, use the load index specified on the door jamb, not a lower one based on the vehicle's curb weight alone.

Some truck owners upgrade to a higher load index than required to add a safety margin for unpredictable loading or rough terrain. This is a personal choice and is safe to do. However, do not go below the manufacturer's requirement under any circumstances, even if you do not plan to use the vehicle's full capacity most of the time.

How to read the load index on a tire sidewall

The tire size and load index appear together in a format like this: 225/65R17 95H. Breaking this down: 225 is the tire width in millimeters, 65 is the aspect ratio (sidewall height as a percentage of width), R means radial construction, 17 is the wheel diameter in inches, 95 is the load index, and H is the speed rating. The load index is always the two or three-digit number when ready before the speed rating letter.

If you are standing at a tire shop or looking at a tire online, scan for this format on the sidewall image or product description. The load index will be clearly visible. If you cannot find it, ask the shop or retailer — they can tell you the load index for any tire size in seconds.

Frequently Asked Questions

Can I use a tire with a higher load index than my vehicle requires?

Yes. A higher load index is safe and straightforward means the tire can carry more weight than your vehicle needs. You will pay more for the tire and may see a slight decrease in fuel economy, but there is no safety risk. Always meet or exceed the requirement on your door jamb sticker.

What if I cannot find the exact load index my vehicle requires?

Use the next higher load index available. If your door jamb specifies a 95 and only a 96 is in stock, the 96 is acceptable. Never go lower than the requirement. If you are unsure, contact the tire retailer or your vehicle's manufacturer for guidance.

Does load index change as the tire wears?

No. The load index is stamped into the tire during manufacturing and remains the same throughout the tire's life, regardless of tread wear. A worn tire with a 95 index is still rated for the same weight capacity as a new tire with a 95 index, though worn tires should be replaced for safety reasons.

Is load index the same as load rating?

Load index and load rating refer to the same thing — the maximum weight a tire can carry. Load index is the number code (like 95), while load rating is the actual weight capacity in pounds (like 1,521 pounds). Both terms describe the tire's weight limit.

Do I need to know the load index for all four tires?

Your vehicle requires the same load index on all four tires. The door jamb sticker specifies one load index for the entire set. Do not mix load indices across the vehicle, as this can cause uneven weight distribution and handling problems.