A Nitto tire size chart helps you narrow a replacement or upgrade to tires that match your wheel, vehicle clearance, load needs, and intended use. Start with the size on the driver-side door placard and your current tire sidewall, then compare the tire’s width, aspect ratio, construction, wheel diameter, load index, speed symbol, and service description. A larger diameter or wider tread may look appealing, but it can create rubbing, alter speedometer readings, reduce steering clearance, or leave the tire under-rated for the vehicle. Use the chart as a fitment starting point, not as permission to install every size listed.
Most Nitto tire size charts organize available sizes by product line and then show the specifications for each size. The chart can tell you which rim diameters a tire is made for and may include overall diameter, section width, tread depth, revolutions per mile, approved rim-width range, load rating, and speed rating. Those details are useful for comparing sizes, but they do not replace vehicle-specific fitment information.
A common metric tire marking looks like 275/55R20 113H. Here is what each part means:
| Sidewall marking | What it identifies | Why it affects fitment |
|---|---|---|
| 275 | Nominal section width in millimeters | A wider tire may contact suspension parts, fender liners, or bodywork. |
| 55 | Aspect ratio; sidewall height is approximately 55% of section width | A lower number generally means a shorter sidewall and can change ride quality and total diameter. |
| R | Radial construction | Radial is the standard construction for modern passenger and light-truck applications. |
| 20 | Required wheel diameter in inches | This must match the diameter of the wheel exactly. |
| 113 | Load index | Shows the tire’s maximum load capacity when used at its specified conditions. |
| H | Speed symbol | Indicates the tire’s tested speed capability under defined test conditions; it is not a target driving speed. |
The width and aspect ratio together determine much of the tire’s overall diameter. For example, changing from a 55-series tire to a 45-series tire on the same wheel can substantially shorten the sidewall, even if the nominal width stays the same. A Nitto tire size chart lets you compare the listed overall diameter rather than trying to estimate the difference from the sidewall code alone.
The number at the beginning of a metric size is nominal. The mounted section width and overall diameter can vary with the approved wheel width, inflation pressure, production tolerances, tread depth, and the measuring method used by the manufacturer. A tire mounted on a wider approved wheel can measure wider and may sit slightly differently than it does on the chart’s measuring rim.
For clearance-sensitive applications, use the chart’s published dimensions as a planning reference, then verify the measuring rim and compare the result with your current setup. This is especially important if your vehicle has aftermarket wheels, a suspension lift or lowering kit, wheel spacers, modified brakes, or non-original alignment settings.
Nitto tires can be listed in more than one sizing system. Reading the format correctly matters because two sizes that look similar may have different intended service categories and load characteristics.
| Size format | Example format | Common use | What to check closely |
|---|---|---|---|
| Passenger metric | 255/50R20 | Cars, crossovers, and many SUVs | Load index, speed symbol, total diameter, and wheel-width range |
| Light-truck metric | LT275/65R18 | Pickups, work vehicles, and some off-road applications | Load range, inflation requirements, weight, and ride trade-offs |
| Flotation | 35x12.50R17LT | Lifted trucks, Jeeps, and off-road-oriented builds | Overall diameter, section width, backspacing, steering clearance, and load range |
A flotation size such as 35x12.50R17LT is read as an approximately 35-inch overall diameter, 12.50-inch nominal section width, radial construction, 17-inch wheel diameter, and light-truck service designation. It is often easier to compare overall height at a glance than metric sizing, but it still does not guarantee that the tire will clear your fenders, suspension, or steering components.
The LT designation deserves attention. Light-truck tires are often selected for durability, heavier loads, towing, or rougher terrain. Depending on the specific tire and size, they may require higher inflation pressures and can weigh more than a passenger-rated alternative. That can affect ride comfort, braking feel, fuel use, and unsprung weight. Do not assume an LT tire is automatically an upgrade for a lightly used daily-driver SUV.
Look for the tire and loading information placard, usually located on the driver-side doorjamb or door edge. It identifies the original tire size or sizes, recommended cold tire pressure, and vehicle load information. Your owner’s manual may also identify approved alternate sizes, spare-tire limitations, and requirements for staggered wheel-and-tire setups.
The placard is more useful than relying on what happens to be installed on the vehicle today. Previous owners, tire shops, or aftermarket wheel packages may have changed the size. A current tire could be physically mountable yet unsuitable for the vehicle’s load requirement, all-wheel-drive system, clearance limits, or original handling balance.
When choosing a replacement from a Nitto tire size chart, select a tire with at least the load capacity required by the placard or vehicle documentation. Avoid reducing load capacity simply because the physical dimensions look close. For replacement tires on a single axle, matching or exceeding the vehicle’s specified capacity is particularly important.
Speed symbols should also be considered as part of the original tire specification. They are associated with a tire’s capability under controlled conditions, but they do not override legal speed limits, road conditions, or safe driving practices. If you are moving from an all-season street tire to a more specialized off-road or winter-focused product, compare the complete service description and understand the trade-offs rather than looking at the size alone.
A plus-size setup generally uses a larger wheel and a lower-profile tire while keeping the overall tire diameter reasonably close to the original. This can preserve gearing and speedometer behavior better than increasing the total diameter substantially. It can also reduce sidewall height, which may sharpen steering response but make the ride firmer and leave the wheel more exposed to pothole damage.
Going taller is common on trucks and off-road builds, but “it fits” can mean only that it clears while parked. A taller or wider tire may rub during a turn, over a driveway transition, when the suspension compresses, or when carrying a load. Wheel offset and backspacing can move the tire closer to suspension parts or farther toward the fender edge, so a size that works on one truck may not work on another with a different wheel.
The largest tire that can be bolted onto a vehicle may not be the right replacement tire. A wide, aggressive-looking tire can increase road noise, reduce wet-weather manners in some conditions, add weight, and complicate rotations if the vehicle has limited clearance. A taller tire can also interfere with factory gearing and may create contact under suspension compression that is not obvious in a quick parking-lot inspection.
For a daily driver, staying close to the original overall diameter is often the simplest route to predictable speedometer behavior, clearance, braking balance, and tire availability. For a truck used for towing, load capacity and inflation requirements should take priority over appearance. For an off-road build, clearance, wheel geometry, suspension travel, and intended terrain may justify a different size, but the setup should be checked as a complete system.
| Driver priority | Usually sensible approach | Main benefit | Verify before buying |
|---|---|---|---|
| Everyday commuting | Stay with the placard size or a closely matched overall diameter | Predictable ride, clearance, and instrument accuracy | Load index, speed symbol, and seasonal suitability |
| Performance-oriented street driving | Consider a wheel-and-tire package with a controlled diameter change | Potentially quicker steering response | Wheel width, offset, sidewall protection, and ride quality |
| Towing or carrying cargo | Prioritize the required load capacity and appropriate service type | Better match for the vehicle’s working demands | Placard requirements, inflation guidance, and axle limits |
| Off-road use | Choose dimensions around terrain, clearance, and suspension design | Potentially more ground clearance and traction options | Full-lock clearance, compression clearance, gearing, and legal requirements |
A Nitto tire size chart describes the tire, not every vehicle, wheel, lift kit, or brake package it might be installed with. Use it alongside a vehicle fitment guide and an in-person inspection where the change is substantial. This matters even more for non-stock wheels because offset and backspacing can change the tire’s position by enough to create a problem.
A 20-inch tire fits a 20-inch wheel only if the tire’s final number is 20, but that says nothing about width, sidewall height, load rating, or clearance. Multiple tire sizes can mount on the same diameter wheel, and they can behave very differently on the vehicle.
A 285-width tire is nominally wider than a 275-width tire, but the aspect ratio and wheel width can make the total diameter change more or less than expected. Compare the manufacturer’s published section width and overall diameter instead of assuming the first number tells the whole story.
A tire needs a wheel width within its listed approved range. Mounting a tire on a wheel outside that range can change its shape and may affect handling, wear, or clearance. The wheel’s diameter being correct is only one part of compatibility.
Replacing one damaged tire with a different overall diameter can be a concern on vehicles that closely monitor wheel speeds or use all-wheel drive. Check the owner’s manual and consult a qualified professional before mixing sizes, construction types, or substantially different tread depths.
Begin with the tire and loading information placard on the driver-side door area, then compare it with the owner’s manual. The size on the current sidewall is useful for reference, but it may not be the original or recommended specification if the vehicle was modified or purchased used.
Possibly, but a size being available from Nitto does not mean it fits every vehicle with that wheel diameter. Compare overall diameter, section width, load capacity, approved rim width, and the vehicle’s actual clearance before purchasing.
Not necessarily. Traction also depends on tread design, rubber compound, temperature, road surface, tire pressure, vehicle weight, and the tire’s intended use. A wider tire may introduce clearance, hydroplaning, noise, or weight trade-offs depending on the application.
LT refers to light-truck service in a tire size designation. These tires are commonly used where heavier-duty construction or load capability is needed, but their inflation needs, weight, and ride characteristics can differ from passenger-rated tires. Match the tire to the vehicle’s specified load requirements and real use.
Do not guess based on size alone. Start with the cold pressure on the vehicle placard unless a qualified tire professional has determined a different pressure that safely supports the vehicle’s axle loads with the selected tire. Never use the sidewall maximum pressure as a routine target pressure.
A Nitto tire size chart is most useful when you read beyond the large size numbers. Match the correct wheel diameter, retain adequate load capacity, compare published diameter and width, and confirm the tire is approved for your wheel and vehicle. If you are changing size for appearance, off-road clearance, towing, or a different wheel package, have the complete setup checked before installation. The right Nitto tire size is the one that meets your vehicle’s requirements and your actual driving needs without compromising clearance or safe load support.