Tire Size 275/70r18 in inches
Tires are a critical component of any vehicle, as they are the only contact point between the vehicle and the road. The correct tire size can enhance your vehicle’s performance, fuel efficiency, and ride comfort.
275/70r18 in inches
Below is a table displaying the measurements of a tire with the size of 275/70r18 in inches.
Feature | Metric | Inches |
---|---|---|
Overall Diameter (Tire Height) | 843 mm | 33.2″ |
Tread Width | 275 mm | 10.8″ |
Rim Diameter | 457.2 mm | 18″ |
Sidewall Height | 193 mm | 7.6″ |
Circumference | 2647 mm | 104.2″ |
Revolutions | 378 per km | 608 per mile |
Breaking Down the Tire Size
The 275/70r18 is equivalent to 33.2×10.8R18 in inches. To understand the tire size better, let’s break down the alphanumeric code “275/70r18”:
- “275” refers to the tire’s tread width in millimeters, which is the width of the tire’s contact patch with the road.
- “70” denotes the aspect ratio, the percentage that the tire’s sidewall height is off the tread width.
- “R” stands for radial construction, which is the most common type of tire construction in modern tires.
- “18” indicates the wheel diameter in inches, the wheel size the tire is designed to fit.
Alternative Tire Size (275/70r18)
It’s commonly suggested to pick replacement tires that possess a diameter measurement that’s within 3 percent of your current tires.
Tire Size | Overall Diameter | Difference |
---|---|---|
305/60R18 | 32.4″ (823 mm) | -2.4% |
285/65R18 | 32.6″ (827 mm) | -1.9% |
265/70R18 | 32.6″ (829 mm) | -1.7% |
375/50R18 | 32.8″ (833 mm) | -1.2% |
295/65R18 | 33.1″ (841 mm) | -0.2% |
325/60R18 | 33.3″ (847 mm) | 0.5% |
305/65R18 | 33.6″ (853 mm) | 1.2% |
285/70R18 | 33.7″ (857 mm) | 1.7% |
Tire Height
The overall diameter of the 275/70r18 tire size is 843 mm (33.2 inches). This measurement represents the total height of the tire from the ground to the top of the tread when mounted on a wheel and inflated to its recommended air pressure. This dimension plays a crucial role in determining vehicle ground clearance, gear ratios, and speedometer accuracy.
Tread Width
As mentioned earlier, the tread width for this tire size is 275 mm (10.8 inches). Tread width affects the tire’s grip, handling, and traction performance. A wider tread width generally provides better stability and cornering capabilities, while a narrower tread width often results in lower rolling resistance and improved fuel efficiency.
Rim Diameter
The 275/70r18 tire is designed to fit on an 18-inch diameter wheel, or 457.2 mm in metric measurements. The rim diameter dictates the size of the wheel on which the tire can be mounted and plays a significant role in the overall appearance and performance of the vehicle.
Sidewall Height
The sidewall height of a 275/70r18 tire is 193 mm (7.6 inches). This measurement is calculated by multiplying the tire’s tread width (275 mm) by the aspect ratio (70%). The sidewall height directly impacts the tire’s ride comfort and handling, with taller sidewalls generally offering a smoother ride and shorter sidewalls providing better cornering capabilities and responsiveness.
Circumference
The circumference of the 275/70r18 tire is 2647 mm (104.2 inches). This measurement is the distance around the outer edge of the tire and is important for calculating vehicle speed and distance traveled.
Revolutions
A 275/70r18 tire completes 378 revolutions per kilometer (608 revolutions per mile). This figure is essential for calculating the tire’s effective gear ratio and speedometer calibration.
Tire Construction
The “R” in the 275/70r18 tire size denotes radial construction, which is the most common type of tire construction today. Radial tires feature steel belts running perpendicular to the tread, providing enhanced strength, durability, and improved handling. Radial tires also offer better fuel efficiency and longer tread life compared to bias-ply tires.
Our Observation
The 275/70r18 tire size is a versatile choice for truck and SUV owners, balancing performance, durability, and aesthetics. With a tread width of 275 mm (10.8 inches), these tires offer ample grip and stability on various road surfaces.
The sidewall height of 193 mm (7.6 inches) contributes to a comfortable ride, while the 18-inch wheel diameter ensures compatibility with many truck and SUV models.
The overall diameter of 33.2 inches allows for increased ground clearance, making this tire size suitable for off-road adventures and challenging terrain. The radial construction of these tires enhances their strength and durability, offering longer tread life and improved fuel efficiency.
In summary, the 275/70r18 tire size is an excellent option for drivers seeking a balance between on-road performance and off-road capabilities. With its generous dimensions and radial construction, this tire size delivers a comfortable ride, reliable grip, and enhanced durability, making it a popular choice for truck and SUV enthusiasts.

Meet Caitlin McCormack, a Tire Size Expert and Blogger Passionate About Everything Related to Tires. With Years of Experience in the Tire Industry, Caitlin Has Become an Expert in Tire Sizes and Their Impact on Vehicle Performance.