# A Beginner’s Guide To How to Measure Tire Width

Measure your tire width from one end of the tire to the other. If you can’t find a tire width number on the sidewall, calculate it on your own. The tire width is measured from endpoint to endpoint. If your tire is not connected to your car, stand it vertically while you measure.

You can use a ruler or measuring tape to measure a tire’s width.

Locate the width of your tire on the sidewall. The size of your tire will be located on the side of your tire. Write down the width number listed on the side.

For example, if it says “215” on the side, this means that you have 215 mm of tire width.

## How do you tell the width of a tire & How to Measure Tire Width?

The width of the tire is measured in millimeters from sidewall to sidewall. The first three-digit number in the tire size refers to the tire width. For instance, in a size P215/65 R15 tire, the width is 215 millimeters.

The aspect ratio of the tire (the second number) is a ratio of the height to the width. In this example, the height is 65 percent of the width (65 percent of 215 millimeters = 140 millimeters). The rim diameter, or wheel size, is measured in inches.

The speed rating indicates how fast a tire can go under ideal conditions. Every passenger car tire sold in North America has a speed rating on its sidewall that tells you what speed it was built for.

Speed ratings range from A (lowest) to Y (highest), with codes Z and W indicating speeds above 149 mph and 168 mph respectively. Speed ratings are provided by the manufacturer and not subject to any type of testing by government agencies or independent testing groups like Consumer Reports.

## How to tell rim size on tire?

When you’re buying a new tire, it’s important to know how it measures up to others you are considering. Rim size is stamped on the back of the hub, and it is often referred to as the “measured size” of the rim because it indicates its manufacturer’s assigned measured diameter, width, and bolt pattern.

The rim size on a tire is stamped on the back of the hub, and this is what you’ll use to get the correct fit. The three sizes are as follows:

Diameter – measures the diameter of the tire, in inches

Width – measures width across the crown of the tire (the part of the tire that looks like a “C”)

Bolt pattern – indicates whether or not it will accommodate the standard rim bolt pattern. In other words, if you have a 4-inch rim, it won’t accept 4-inch tires. It will only accommodate tires with a 4/114 bolt pattern.

## What is a 32 tire?

The metric designation for tire sizes was introduced to provide an easier way to find tires that fit a particular vehicle. With the standard system, a 32′ is always a 32′ but, with the metric system, a 265/70/16 is a 30½’ diameter tire, for example, and a 265/75R17 is a 32½’ diameter tire.

It’s important to make sure your tires are the right size for your vehicle. It’s also critical to buy tires with proper load ratings, meaning they can support the weight of your vehicle as well as its cargo and passengers.

It’s a bit more complicated than that. With the standard system, a 32′ is always a 32′ but, with the metric system, a 265/70/16 is a 30½’ diameter tire, for example, and a 265/75R17 is a 32½’ diameter tire.

Here are the actual diameters of some tires in both systems:

265/70 R16= 30.6 inches

265/75 R16= 31.65 inches

265/75 R17= 32.7 inches

265/85 R16= 34.45 inches

## How to figure out tire size?

Tire Diameter = Wheel Diameter + 2 × Section Height

The aspect ratio and tire width are measurements acquired from the tire code. The tire width is the 3-digit number preceding the forward-slash (/) in the tire code in units of millimeters.

The aspect ratio is unique because it does not have a standard unit of measurement. Instead, it is a ratio of the tire’s section height to its section width (height/width). For example, when converting a metric tire size to inches, the overall diameter would be calculated as follows:

[(16″ × 25.4) + (2 × 50)] ÷ 25.4 = 27.5″

1. Begin with finding the tire aspect ratio following the tire width. This is normally a two-digit number and is the numerical value that follows the forward-slash (/) in the tire code. For example, P225/50 R16 91V has an aspect ratio of 50.

2. Multiply the tire aspect ratio by 2 to get your section height (in inches). For example: 50 × 2 = 100mm or 3.93-inches.

3. Find your wheel diameter from the last two digits of the tire size code. For example, 225/50 R16 91V has a 16-inch wheel diameter.

4. Add your two results together to get your approximate tire diameter (in inches). For example: 3.93 + 16 = 19.93-inches

## How to determine tire width?

The first number in a tire size is the width. The width of a tire is measured in millimeters from sidewall to sidewall. A tire that is 205 mm wide will have “205” as its first number. The width of the wheel that the tire is designed to fit on is also included as part of the size description.

The second number in a tire size is the aspect ratio. The aspect ratio tells you what percentage of the tire’s width makes up the sidewall height, or how tall its sidewalls are. For example, if a tire’s size is described as P205/55R16, the second number “55” means that the height is equal to 55% of its width of 205 mm.

The third number in a tire size is the diameter of the wheel rim, which it fits on to, measured in inches.

For instance, in a size P215/65 R15 tire, the width is 215 millimeters, and the height is equal to 65% of 215 millimeters (or 140 millimeters). The 15 indicates that this tire would fit on a 15-inch wheel rim.

## How to measure wheel width?

Measuring rim width is pretty simple to do! Just take a ruler, yardstick, or tape measure and measure the distance from bead seat to bead seat. The rim width is also included in the wheel size, which you can find stamped on the back of the wheel, or in your owner’s manual.

For instance, a 15×6 wheel will have 6 inches of rim width. A 15×8 wheel would have 8 inches of rim width.

What difference does it make?

The rim width needs to be compatible with the tire for optimum performance and handling characteristics. Most tire manufacturers will provide a chart showing what range of rim widths are appropriate for each tire size.

If you’re looking for a new set of rims, one of the first questions you’ll need to answer is how wide do you want the rim to be? Rim width is essential when it comes to fitting larger tires as well as overall performance. To measure rim width, all you’ll need is a ruler or measuring tape and a few minutes.

## How wide is a 225 tire?

To answer the question, the width of a 225 tire in inches is 8.86 inches, or approximately 8 and 7/8th inches wide. You can use the tire size calculator below to see just how much wider than 225 tires is compared to other tires that are on your vehicle now.

We’ve added a tire comparison tool for you so you can see how much wider a 225 tire is compared to your current tires. This will help you make an informed decision about whether or not a 225 tire will fit on your vehicle without rubbing issues. We’ve also added a wheel width calculator for you.

The section width can be converted to inches by dividing the width in millimeters by 25.4 like so: (225 millimeters) / (25.4 mm/in) = 8.86 inches.

The section height is measured from the rim to the tread but is not always expressed. For example, a section height of 0% means that the tire is a flat-bead design and does not have a sidewall.

## How tall is a 225 75r16 tire?

225/75R16 Height – How tall is a 225/75R16 tire in inches? This tire size is 29.287 inches tall.

225/75R16 Width in inches – How wide is a 225/75R16 tire? This tire size is 8.858 inches wide (tread width).

225/75R16 Diameter – The diameter of a 225/75R16 tire is 29.725 inches.

225/75R16 Circumference – The circumference of a 225/75R16 tire is 94.077 inches.

225/75R16 Sidewall Height – The sidewall height of a 225/75R16 tire from the edge of the rim to the tread is 23.432 inches or 1.9536 feet.

The size 225/75R16 is a tire that is widely used on pickup trucks and SUV vehicles. The tire size features the iconic “R” which indicates this is a radial type of tire. The “R” also means that the width of the tire’s sidewall will be between 10% and 50% of its width. This means that the height of the sidewall would be between 8″ and 16″.

## FAQ

### #1. How does the tire size comparison calculator work?

The tire size comparison calculator takes the measurements of two tires and compares the diameter, width, sidewall, circumference, and revolutions per mile. Then as a bonus, it shows examples of your speedometer reading with the first tire, and the actual speed you’re traveling if you were to install the second tire. It’s important to note that this calculator only makes estimations of your speedometer variance and should not be used in place of consulting with a certified mechanic or tire expert.

### #2. How do you know what size your tires are?

Tire size is a combination of metric numbers, letters, and symbols that, when put together, can tell you all the information you need to know about the tire’s size and purpose. Generally, this information is most specific when it comes to your tire size; section width, aspect ratio, and wheel size. If you don’t know your tire size, you can just read the sidewall of your current tires. It’s suggested that you snap a photo or write it down somewhere safe.

### #3. How to use the tire calculator?

In the top row, you need to select the size of the tires that are on your car at the moment. These indicators can be easily found on the sidewalls of your tires. In the first box, you need to choose tire width in inches. The second box is for the height and width ratio in percentages. Depending on how much information you want to gain, you can fill in either one or both boxes. To learn more about motorcycle and car tire sizes, read our article explaining these dimensions.

### #4. What do the numbers on a tire mean?

The number is the load rating or the amount of weight that it can handle. The letter is the speed rating or the maximum speed the tire is built for. As an example, a tire rated 90R could safely support 1,323 pounds at up to 106 mph. The Uniform Tire Quality Grading System (UTQGS) provides ratings for traction, temperature, and treadwear from A-C based on standardized tests developed by the National Highway Traffic Safety Administration (NHTSA).

## Conclusion on How to Measure Tire Width

Tires come in a variety of sizes. Some cars use the same size tire for all four wheels, while other cars use a different size for the rear wheels or even all four. Light trucks and SUVs often have a unique tire size for each wheel.

It’s important to know the specifications of your tires so that you can measure them to make sure they are inflated properly and that you buy the correct replacement tires when it’s time to replace worn tires.

Read your vehicle’s owner manual to determine what type of tires you should use on your car and if there is more than one acceptable tire size.