245/30R20 Tire Size Guide

The 245/30R20 code identifies a metric radial tire with four main pieces of information. The 245 is the section width in millimeters, the 30 is the aspect ratio, meaning the sidewall height is 30 percent of the width, the R indicates radial construction, and the 20 means the tire fits a 20-inch wheel.

Unlike older alphanumeric or numeric sizing systems, 245/30R20 gives a direct width measurement and a direct profile measurement right in the code. What it does not tell you by itself is wheel width, load capability, or whether a particular version is correct for every vehicle using this size, so those details still need to be checked from the actual tire and wheel package.

The 245/30R20 fits a 20.0-inch wheel, which equals 508.0 millimeters at the bead seat diameter. The wheel diameter must match exactly, because the tire is engineered around that 20-inch mounting dimension and will not seat properly on any other diameter.

Wheel diameter and wheel width are separate measurements, and buyers need to confirm both before installation. A 20-inch diameter alone does not guarantee a correct setup if the wheel width, offset, brake clearance, or fender clearance are wrong, so the full wheel and vehicle package should be reviewed as a system rather than by diameter alone.

The 245/30R20 has a section width of 245 millimeters, which converts to 9.65 inches. Section width measures the tire at its widest point from sidewall to sidewall when inflated, not the tread face that actually meets the road.

Clearance decisions should be based on section width first, because sidewall bulge is often what comes closest to suspension parts, fender lips, and inner wheel housings. Tread width is usually narrower than section width, so a buyer who measures only the tread can underestimate how much room the full tire package really needs.

The 245/30R20 has an overall diameter of 25.79 inches, or about 655.1 millimeters. That figure combines the 20-inch wheel diameter with two sidewalls measuring 2.89 inches each.

Overall diameter matters because it affects ride height, wheel-opening fill, and the relationship between the tire and the speedometer calibration. When comparing replacement sizes, diameter is one of the first numbers to review, since a meaningful change can alter stance and can also change how much room the tire has during suspension travel or steering movement.

The 245/30R20 has a sidewall height of 2.89 inches, which is 73.5 millimeters. Since the aspect ratio is 30, the sidewall is 30 percent as tall as the tire is wide.

A sidewall this short is part of what gives the size its low-profile character. Drivers often notice quicker steering response and a sharper visual stance from a shorter sidewall, but they should also expect less cushioning over rough pavement than with a taller profile, especially if the vehicle uses firm suspension tuning or large-diameter wheels.

The 245/30R20 turns about 782.0 revolutions per mile. That number comes from the tire’s 81.02-inch circumference and helps describe how often the tire rotates over a fixed distance.

Revolutions per mile become important when comparing alternate sizes, because a tire that turns more or fewer times per mile can change speedometer and odometer readings. Buyers considering a substitute should compare revolutions per mile together with overall diameter, since both numbers help show whether a different size will stay close to the original rolling profile.

No. The 245/30R20 fits a 20-inch wheel by diameter, but that alone does not make it a universal fit for every vehicle with 20-inch wheels. Width, offset, brake package, suspension travel, and the available space at the fender and inner wheelhouse all affect whether this size works correctly.

Vehicles that use this size are typically performance-oriented and can be sensitive to small changes in tire dimensions. Before treating the 245/30R20 as a replacement, compare the existing tire size, confirm the wheel specifications, and check both static and turning clearance so the new tire does not create rubbing, stance, or drivability issues.

The most important checks for the 245/30R20 are wheel diameter, wheel width, section width clearance, overall diameter, and load requirements. Because this is a short-sidewall performance size, buyers should also pay close attention to brake clearance, suspension movement, and any risk of contact at full steering lock or under compression.

Start by matching the 20-inch wheel diameter, then compare the 9.65-inch section width and 25.79-inch overall diameter to the current setup. On low-profile fitments, even modest differences in wheel width or offset can change how the sidewall sits relative to the fender, so measuring the complete wheel-and-tire package is more useful than relying on size code alone.

The 245/30R20 can make sense on a build that prioritizes modern road manners and a contemporary low-profile look, but it is not automatically the right choice for a judged restoration. Radial construction can improve everyday drivability, yet originality standards may call for a different type of tire depending on the vehicle and the era being represented.

A buyer restoring a vehicle for strict authenticity should compare the original documentation, wheel dimensions, and the appearance expected for that period before choosing this size. If the goal is a restomod or a later custom build, the 245/30R20 may be more appropriate, provided the wheel package, clearance, and intended use all support it.

The 245/30R20 is built around a very short 2.89-inch sidewall, so it typically delivers a firmer, more immediate feel than a taller-profile tire. Drivers often notice quicker steering response and less sidewall movement, especially on vehicles already tuned for performance driving.

Ride quality still depends on suspension setup, inflation, wheel width, and road surface, not just the size code. On broken pavement or expansion joints, a 30-series profile usually transmits more impact harshness than a taller sidewall, so buyers replacing a different size should think about comfort expectations as well as appearance and responsiveness.

The 245/30R20 is commonly used on modern street-driven performance cars, so it can be an everyday replacement when the vehicle was designed around this type of low-profile fitment. Its radial construction supports current-road drivability better than older tire formats aimed mainly at period appearance.

Daily-use results depend on more than the size itself. Alignment condition, suspension wear, road quality, load carried, and the exact tire model all influence noise, braking feel, and tire wear, so buyers should treat the 245/30R20 as a vehicle-system decision rather than assuming every car will respond the same way.

With a 25.79-inch overall diameter and about 782.0 revolutions per mile, the 245/30R20 has a rolling profile that directly affects visual stance and the relationship between road speed and wheel rotation. Any move to a taller or shorter substitute can change how full the wheel opening looks and how quickly the tire turns at speed.

A shorter alternative can make the vehicle sit visually lower and can raise engine rpm slightly at a given road speed, while a taller one can do the opposite. Buyers considering another size should compare diameter and revolutions per mile together, because those two measurements tell more about real-world gearing feel than width alone.

The 245/30R20 is available here from Nitto. Even when only one brand is in view, buyers should still compare the exact sidewall markings, load specifications, and intended use of the tire rather than assuming every tire carrying the same nominal size behaves the same way.

Brand choice in a low-profile performance size is usually less about broad marketing claims and more about whether the tire matches the vehicle’s purpose. A street-driven replacement, a visual custom build, and a carefully tuned performance setup can all have different priorities, so consistency between the tire’s construction and the car’s real use matters more than the name alone.

A quality 245/30R20 tire should match the vehicle’s load needs, wheel dimensions, and intended road use while holding the correct overall proportions for the application. On a low-profile radial size like this, buyers should pay close attention to sidewall markings, construction consistency, and how closely the tire’s actual dimensions align with the setup already on the car.

Good selection practice also means evaluating the tire as part of a complete set. Mixing different constructions, very different wear levels, or noticeably different overall diameters across the vehicle can change steering feel and balance, so many owners prefer to keep all four tires closely matched in age, type, and purpose.

Yes, sidewall style can matter, even on a modern performance size. The 245/30R20 shown here uses a blackwall appearance, which suits many late-model applications where the emphasis is on a clean, understated side profile rather than a vintage stripe or lettered look.

Appearance is only one part of the decision, though. A buyer should first confirm that the tire’s dimensions, construction, and service description fit the vehicle correctly, then decide whether the sidewall look supports the build’s overall character, whether that is an original-equipment style replacement or a more customized presentation.

The 245/30R20 should be inspected regularly for air loss, cuts, bulges, cracking, and uneven wear, especially because a short sidewall can hide less visual deflection than a taller tire. On a performance-oriented fitment, curb contact and pothole impacts also deserve close attention because the wheel and tire have less cushioning than a taller-profile setup.

Regular street use calls for routine pressure checks and visual inspections before long trips, not just when a problem is obvious. Uneven shoulder wear, vibration, or repeated pressure loss can point to alignment, wheel damage, or suspension issues, so catching those signs early usually does more for tire life than waiting for tread wear alone.

Occasional use does not stop a 245/30R20 from aging. Time, heat, sunlight, ozone exposure, and storage conditions continue to affect the rubber and internal structure even when tread wear remains low, so a lightly driven tire can still reach replacement age before it looks worn out.

Collector or seasonal-use owners should inspect for surface cracking, hardening, flat spotting, and vibration after the vehicle sits. Storage away from direct sunlight, excess heat, moisture, and electric motors that generate ozone can help slow deterioration, but calendar age still matters and should be considered alongside tread depth and visible condition.

The 245/30R20 is normally a tubeless fitment. Even so, tube use is a wheel-and-tire-system question rather than a size question, so the final setup should always be confirmed against the actual wheel being used and the specifications on the tire itself.

Modern radial passenger sizes like this are usually paired with tubeless wheels, but damaged rims, specialty wheels, or unusual applications can change what is appropriate. Before mounting, inspect the wheel condition, valve hardware, and bead area, and confirm the intended setup with a qualified tire professional if there is any uncertainty.

The 245/30R20 should be replaced when inspection shows cracking, bulges, exposed cords, repeated air loss, impact damage, or tread wear severe enough to compromise wet or dry traction. A low-mileage tire should not be kept in service just because the tread still looks deep if age or condition suggests the structure has deteriorated.

Before highway travel, inspect both the tire and wheel for signs of damage from potholes or curb strikes, since low-profile sizes can transmit those impacts more directly. Buyers should use current sidewall markings, visible condition, and professional inspection when needed to decide whether continued road use is appropriate.

Before highway use, buyers should confirm that the 245/30R20 matches the vehicle’s required size range, wheel specifications, and service description, and that the tire is in sound condition with no visible damage or abnormal wear. The sidewall markings on the actual tire should also be reviewed so they match the intended use of the vehicle.

Highway stability and durability depend on the complete setup, including alignment, inflation maintenance, suspension condition, and load carried. A performance radial can behave very differently on a properly sorted car than on one with worn bushings or poor alignment, so roadworthiness should be evaluated as a system rather than by size code alone.

Yes. Buyers should review the exact sidewall markings on the 245/30R20 they intend to use, then compare them with the vehicle placard, owner documentation, and any local inspection or road-use requirements that apply where the vehicle is operated. Size alone does not confirm every regulatory or service-detail requirement.

If the vehicle is modified, lowered, or running non-original wheels, those changes make it even more important to verify wheel compatibility, load needs, and clearance before road use. A careful comparison of the full wheel-and-tire package is more useful than relying on nominal size alone when legality, drivability, and safe operation all matter.