315/75r18 In Inches – Tire Size, Rim Fitment & Best Tires

The 315/75R18 tire has an overall diameter of approximately 36.9 inches, a section width of roughly 12.4 inches, and is designed to be mounted on an 18-inch diameter rim. The equivalent tire size in the high flotation system is 36.9×12.4R18.

What does 315/75r18 Tire mean?

Before we move on, let’s make sure we understand what the tire size 315/75r18 means. Just like everything else, numbers on tires have their meaning, and no, they are not the secret code to an alien language.

Let’s break it down with a simple table.

Tire NumberIts Explanation
315This is the tire’s width in millimeters, measured from sidewall to sidewall. Imagine a tire lying flat, the width would be the measurement across its tread.
75Known as the aspect ratio, this represents the height of the tire’s sidewall as a percentage of the width. In this case, the tire’s height is 75% of 315mm.
RThe ‘R’ stands for Radial, indicating the construction of the tire. Radial tires are pretty much the standard these days, thanks to their durability and resistance to heat.
18This number represents the diameter of the wheel (or rim) in inches that the tire is designed to fit. Our tire fits on an 18 inch rim.

What is 315/75r18 Tire in inches?

315 75r18 Tire in inches

Now that we have the basic understanding, let’s get to the heart of the matter. The main question we’re here to answer – What is 315/75r18 tire size in inches?

Well, for starters, the width (315mm) is about 12.4 inches. Now, to get the sidewall height, we take 75% of 315mm (the aspect ratio remember?), which is about 9.3 inches.

315/75r18 Tire Dimensions in inches and Millimeters

Time for a little more detail. Here’s a table that displays the various measurements of a 315/75r18 tire in both inches and millimeters:

Tire Diameter34.6880
Section Width12.4315
Rim Diameter18457.2
Sidewall Height9.3236.25
Revolutions per Mile583362.1

A Deeper Dive into the 315/75r18 Tire Specifications

Now that we have the basics covered, let’s take a deeper dive into the fascinating world of the 315/75r18 tire. I know what you’re thinking, “Wow, this is getting exciting!” Well, hold onto your seats because we’re about to uncover some mind-blowing details about this tire size.

Tire Width of 315/75r18

Let’s start with the tire width. The 315 in 315/75r18 represents the width of the tire in millimeters. It’s like the tire is flexing its muscles, boasting a proud width of approximately 12.4 inches. That’s right, this tire is wider than a slice of your favorite pizza! Now you can conquer the road with confidence, knowing that your tires have a solid grip on the asphalt.

Tire Height of 315/75r18

Next up, we have the tire height. The 75 in 315/75r18 indicates the aspect ratio, which is the tire’s height as a percentage of its width. In the case of our beloved 315/75r18, it proudly stands at around 75% of its width. This translates to a tire height of roughly 9.3 inches. That’s like having a mini mountain range right under your vehicle. Take that, uneven terrain!

Sidewall Height of 315/75r18

Ah, the sidewall height. It’s like the tire’s fashion statement, showcasing its style and personality. For our mighty 315/75r18, the sidewall height measures approximately 9.3 inches. That’s more than just a fashion statement; it’s like having the perfect amount of cushioning to absorb those bumps and shocks along the way. It’s like riding on a cloud, or at least the closest thing to it.

Rim Diameter for 315/75r18

Now let’s talk about the rim diameter. The 18 in 315/75r18 represents the size of the wheel or rim that this tire is designed to fit. It’s the Goldilocks of rim sizes, not too big and not too small, just right! So, if you’re rocking an 18-inch rim, consider yourself lucky because you have the perfect match for the 315/75r18 tire.

Tire Circumference of 315/75r18

Ah, the tire circumference, the measurement that wraps it all up. For the 315/75r18, the tire’s circumference measures approximately 108.7 inches. That’s like going on an exhilarating roller coaster ride, except this ride never ends (unless you stop, of course). So buckle up and enjoy the journey, knowing that your tires are giving you the perfect amount of traction and stability.

FAQ’s About 315/75r18 Tire

Ah, the land of burning questions and curious minds! I’m here to satisfy your hunger for knowledge about the magnificent 315/75r18 tire. So, let’s jump right into the most frequently asked questions that are sure to tickle your brain cells.

What vehicles use 315/75r18 Tire?

The 315/75r18 tire size is a popular choice for various vehicles that crave a balance of power and versatility. It’s like the tire equivalent of a superhero costume, ready to tackle any terrain that comes its way. You can find this tire size adorning the wheels of robust trucks, mighty SUVs, and even some off-road beasts. So, whether you’re conquering the concrete jungle or blazing trails through rugged landscapes, the 315/75r18 tire has got your back.

How many revolutions per mile does a 315/75r18 have?

Ah, the magic of revolutions per mile! Picture a 315/75r18 tire, gracefully spinning as it covers the miles. In this case, you can expect this tire to complete approximately 583 revolutions per mile. That’s right, it’s like a tire dance party happening every time you hit the road. So, turn up the music and enjoy the rhythmic motion of your trusty 315/75r18 tires.

Price of 315/75r18 inches Tire?

Ah, the topic that makes wallets quiver and bank accounts cringe. When it comes to the price of the 315/75r18 tire, it’s essential to consider various factors. The brand, tire model, and even local market conditions can influence the price range. On average, you can expect to invest anywhere from $200 to $400 per tire. But remember, this is just a ballpark figure, and prices may vary depending on your location and specific tire preferences. So, prepare your budget accordingly and remember that quality tires are an investment in your safety and driving experience.

What kind of rim does a 315/75r18 tire fit on?

Now, let’s talk about rim compatibility, because not every rim is a perfect match for the 315/75r18 tire. This tire size is designed to fit on an 18-inch rim, also known as an 18×9 rim. So, if you have an 18-inch rim that’s about 9 inches wide, congratulations! You’ve found the perfect companion for your 315/75r18 tire. It’s like they were destined to be together, creating a harmonious blend of style and performance.

How much air should be in 315/75r18?

Ah, the crucial task of keeping your tires properly inflated. It’s like giving your tires a breath of fresh air, quite literally. For the 315/75r18 tire, the recommended tire pressure typically ranges between 35 to 45 PSI (pounds per square inch). However, it’s essential to refer to your vehicle’s owner manual or the tire manufacturer’s guidelines for the specific recommended pressure. Proper inflation ensures optimal tire performance, fuel efficiency, and even tire longevity. So, keep those tires happy and healthy by giving them the right amount of air.

What is a 315/75r18 equivalent to?

Ah, the world of tire equivalents, where sizes become interconnected like a web of possibilities. If you’re looking for an alternative to the 315/75r18 tire size, there are a couple of options worth exploring. The closest equivalent would be the 35×12.50r18 tire size. It’s like finding a sibling tire, sharing similar characteristics and dimensions. This alternative size maintains the same width and overall diameter, making it a suitable substitute for those seeking a similar fit and performance.

Comparison with Similar Tires

Now that we’ve explored the ins and outs of the glorious 315/75r18 tire, it’s time to put it head-to-head with some of its tire brethren. Let’s see how it stacks up against similar tire sizes in terms of performance, versatility, and sheer tire awesomeness.

315/75r18 vs. 35×12.50r18

One of the closest relatives to the 315/75r18 is the 35×12.50r18 tire size. These two sizes share similar characteristics, with the 35×12.50r18 offering a comparable width and overall diameter. It’s like having a sibling tire that can hold its own on the road. So, whether you opt for the 315/75r18 or the 35×12.50r18, you can expect excellent performance and a solid grip on various terrains.

315/75r18 vs. 305/70r18

Another contender in the tire arena is the 305/70r18. While this size differs slightly from the 315/75r18, it still packs a punch in terms of width and overall diameter. The 305/70r18 offers a touch of nimbleness and agility, making it an attractive option for those seeking a balance between on-road performance and off-road adventures. So, if you’re torn between the 315/75r18 and the 305/70r18, rest assured that both sizes offer exceptional capabilities.


After immersing ourselves in the world of the 315/75r18 tire, it’s time to wrap things up with a clear and concise recommendation. Based on the information gathered throughout this article, we can confidently say that the 315/75r18 tire size is an excellent choice for those seeking a combination of power, versatility, and performance.

With its substantial width, solid sidewall height, and ideal rim fitment, the 315/75r18 tire stands tall as a formidable companion for trucks, SUVs, and off-road enthusiasts. Its capability to conquer various terrains, from city streets to rugged trails, is truly impressive.

However, it’s crucial to consider your specific driving needs and preferences when selecting tires. Factors such as climate, driving conditions, and personal preferences should all be taken into account. Consulting with tire professionals and considering user reviews can also provide valuable insights.

In the end, the 315/75r18 tire size remains a popular and reliable choice, delivering a winning combination of performance and style. So, whether you’re cruising down the highway or exploring the great outdoors, let the 315/75r18 tire be your trusty sidekick, ready to tackle any adventure that comes your way.

Choose your tires wisely, my friends, and may the road be ever in your favor!