What a load index tells you about your tires

A load index is a number on your tire that shows the maximum weight that single tire can safely carry. It appears on the tire's sidewall as a two- or three-digit number, usually paired with a speed rating letter. For example, a tire marked "95H" means that tire has a load index of 95 and a maximum speed rating of H (130 mph).

The load index itself does not tell you the weight in pounds or kilograms — it is a code. A load index of 95 means something different from a load index of 96, and you need a chart to convert that number into actual weight. This matters because using a tire with too low a load index for your vehicle can cause the tire to overheat, wear unevenly, and fail while driving.

Your vehicle's owner's manual or the driver's side door jamb lists the load index your tires must meet. You should never buy a replacement tire with a lower load index than what your vehicle requires, though a higher index is safe.

Key Takeaways

  • Load index is a two- or three-digit code on your tire's sidewall that corresponds to maximum weight capacity, found by using a load index chart.
  • Your vehicle's required load index is printed on a sticker inside the driver's door jamb or in the owner's manual, not on the tire itself.
  • A load index of 75 carries roughly 1,389 pounds per tire, while a load index of 100 carries roughly 2,205 pounds per tire — the relationship is not linear.
  • Replacement tires must meet or exceed your vehicle's original load index; using a lower index creates a safety risk.
  • Load index and speed rating are separate codes; a tire can have high load capacity but a lower speed limit, or vice versa.

How load index numbers map to weight capacity

Load index numbers run from 0 to 150, though most passenger vehicles use indexes between 70 and 110. The chart does not increase in even steps — each number jump represents a different weight increase depending on where you are on the scale.

A load index of 75 means the tire can carry approximately 1,389 pounds. A load index of 80 jumps to approximately 1,763 pounds. A load index of 85 is approximately 2,149 pounds. A load index of 90 is approximately 2,601 pounds. A load index of 95 is approximately 3,075 pounds. A load index of 100 is approximately 3,527 pounds.

The reason the jumps are uneven is that load index was designed to cover a wide range of vehicles — from small cars to heavy trucks — in a single numbering system. If you need the exact weight for a specific index, a full load index chart is available from tire manufacturers and automotive reference sites, but for most people, knowing your vehicle's required index and matching it is what matters.

Where to find your vehicle's required load index

Your vehicle does not have a single load index — it has a required load index per tire, and that requirement is based on your vehicle's weight and how that weight is distributed across all four tires.

The easiest place to find this number is on a white sticker on the inside of the driver's side door jamb. This sticker lists tire size, pressure, and load index all together. The load index appears as a number in the tire size code itself — for example, "P225/65R17 95H" means load index 95.

If the sticker is missing or hard to read, your vehicle's owner's manual contains the same information in the tire specifications section. Some vehicles also print it on the fuel door or inside the trunk lid, though the door jamb is the standard location.

The difference between load index and load range

Load index and load range are two different systems, and they are not interchangeable. Load index is the number code system used for passenger car tires. Load range is a letter system (A through F) used for light truck tires, trailer tires, and some specialty tires.

If you drive a passenger car, you will see a load index number. If you drive a truck or SUV, you might see either system depending on the tire type — check your door jamb sticker to see which one your vehicle uses. Do not try to convert between the two; use whichever system your vehicle's sticker specifies.

Why load index matters for tire safety

A tire with too low a load index for your vehicle will flex more than it should under the vehicle's weight. This extra flexing generates heat inside the tire, which can cause the rubber to break down faster, the sidewalls to weaken, and in extreme cases, the tire to fail suddenly while driving.

Overloading a tire also causes uneven wear — the center of the tread wears faster than the edges — and reduces fuel economy because the tire is working harder. Over time, an underrated tire becomes a blowout risk, especially on highways or in hot weather.

Using a tire with a load index higher than required is safe and common. Many people buy tires rated for heavier vehicles than they own, which provides a safety margin and can extend tire life. The risk only goes in one direction: too low is unsafe, too high is fine.

Load index versus speed rating

Speed rating and load index are printed together on the tire sidewall, but they measure completely different things. Load index is about weight capacity; speed rating is about how fast the tire can safely go.

A tire might have a load index of 95 (high weight capacity) but a speed rating of T (118 mph maximum). Another tire might have a load index of 85 (lower weight capacity) but a speed rating of W (168 mph maximum). You need both numbers to match your vehicle's requirements, and they do not depend on each other.

Your vehicle's door jamb sticker lists both the required load index and the required speed rating. When buying replacement tires, check both numbers against the sticker — do not assume that a tire meeting the load index will also meet the speed rating, or vice versa.

What to do when replacing tires

When you buy replacement tires, bring the sticker from your door jamb or a photo of it to the tire shop. Tell the shop the load index and speed rating you need, and they will show you tires that meet those specs.

If a tire shop suggests a tire with a lower load index than your vehicle requires, ask them why and get a second opinion. A lower index might be cheaper, but it is not a safe trade-off. If you cannot find a tire that meets your exact load index in the size and brand you want, a higher index is the right choice.

Some vehicles come with all-season tires that meet the minimum load index, while others come with performance or winter tires that exceed it. When replacing, you can choose any tire that meets or exceeds the requirement — you are not locked into the original tire type.

Frequently Asked Questions

What happens if I use a tire with a load index that is too low?

The tire will flex more under your vehicle's weight, causing it to overheat and wear unevenly. Over time this weakens the tire structure and increases the risk of a blowout, especially in hot weather or on long highway drives. The tire may also reduce your fuel economy because it is working harder.

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

Yes. A higher load index is safe and actually common — many people buy tires rated for heavier vehicles than they own. This provides extra safety margin and can extend tire life. The risk only goes in one direction: too low is unsafe, too high is fine.

Where exactly is the load index number on the tire?

It is on the sidewall of the tire, printed as part of the tire size code. For example, in "P225/65R17 95H", the 95 is the load index and the H is the speed rating. You will see this same code on your vehicle's door jamb sticker, which is the easiest place to find your vehicle's requirement.

Is load index the same as load range?

No. Load index is a number system (0–150) used for passenger car tires. Load range is a letter system (A–F) used for truck and trailer tires. Check your door jamb sticker to see which system your vehicle uses, and do not try to convert between them.

Can I mix tires with different load indexes on the same vehicle?

It is not recommended. All four tires should meet or exceed your vehicle's required load index. Mixing different indexes can cause uneven wear and handling problems. If you must replace only one or two tires, match the load index of the tires already on your vehicle.