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Finding The Right Tire Size

How to Search for the Right Tire Size With the Help of a Tire Size Finder


A tire size finder is a calculator that helps you to find the right size of tire fit for your vehicle. The tire size finder works in two different ways including the use of information in the vehicles and the use of the numbers that are seen on the side walls of the tire. It takes the dimensions of two tires and makes comparisons between the tires over the width, circumference, sidewall, diameter, and revolutions per mile. Then, it demonstrates the reading of the speedometer with the first tire, and the concrete speed of the tire while installing the second tire.

Let’s check the usefulness, and method to read the tire along with the way of calculating the accurate size of the tire.

The Idea of the Tire Size Finder and Its Working Method to Read the Tire

The tire size finder is helpful to calculate and correct the speedometer. This would be valuable if the car drivers plan to run larger tires than the ordinary ones and want to identify the speed of the tire that they are riding along with a proper speedometer reading. A bigger tire always acquires a larger circumference, therefore riding at a remote distance for each of the revolutions. A speedometer reading through the tire size finder helps to get a distance parameter to the drivers. In this way, you can ride faster than the reading of your speedometers by installing larger tires, and slower than the reading of your speedometers by installing smaller tires.

The tire size finder also includes a diameter calculation that gives an overall suggestion when buying new tires for your car or changing the existing ones. For calculating the size of your tire, the calculator suggests several tire sizes that are within an inch bigger or smaller than the entered tire size. In this aspect, you need to select the list of tires according to budget cost which makes it possible to find the tire with the perfect size at the best reasonable prices.

Method to Read the Tire Size With the Help of a Tire Size Finder

While going to find a new tire for your vehicle, first, you need to understand the method to read the tire size of your vehicle. However, reading the tire sizes can be a bit confusing which can be cleared by using the tire size finder as they use metric or P-metric tire size terms to calculate the tire size. The P-metric size term contains several important pieces of information about the tire that can be easily measured through the tire size finder.

Vehicle Type- The first note of the tire size term is the vehicle type that denotes the type of designation used in the tire. The ‘P’ designates that the dimensions are a P-metric size along with the dimension of LT-metric types and euro metric.

Section Width- The first three statistics in the tire size term before the slash (“/”) signify the tire breadth in millimeters. This is the width parameter from one sidewall to another sidewall which is also called the tread width and the section width.

Aspect Ratio– The two or three figures of tire size dimension sit after the slash (“/”) which designates the aspect ratio of the tire. The aspect ratio involves the proportion of the width and height of the tire and is applied to understanding the tire height by using the formula to calculate the tire size.

Construction– This is the figure of the aspect ratio that designates the tire construction. An ‘R’ is the most common letter in the tire construction figure and signifies a radial construction and “D” is to denote the diagonal bias construction in construction.

Rim Diameter- The next number of tire size diameters represents the rim diameter which suggests the size of the wheel calculated in inches.

Load Index– After reading the rim diameter, another figure is the load index of the tire. This load index involves a code that links to a load evaluation for the tire.

Speed Rating– The final figure in the tire size calculating term is the speed rating that links to the rating for the tire when the vehicle is being ridden at its extreme speed. It ensures the tire has a rating that is greater than or equivalent to the speed capability of the car.

How to Calculate Your Tire Size in a Tire Size Finder

You would identify the appropriate size of the tire when you properly use the tire size finder. These include several formulas to calculate the accurate size of a tire in a tire size finder.

Formula to Calculate Sidewall Height

The sidewall height calculation is resulted by scheming the width section of the tire and the aspect ratio. The formula to get the size of sidewall height is,

sidewall = (section width × aspect ratio)/100

The result of the calculation will be in millimeters while showing the measurement of the sidewall height and you have converted it into inches through the help of the calculator itself.

Formula to Calculate Tire Height

You would find the height of the tire by applying the sidewall dimension in the formula. The formula to analyze tire height diameter includes:

Tire height diameter = (2 × sidewall) + rim diameter

Formula to Calculate Tire Circumference

The circumference of a tire helps to calculate the error in the speedometer of the tire. The driver can find the circumference of the tire by using the tire height diameter in a simple calculating formula, which is-

Circumference of tire = tire height diameter × π (Pi)

Here, Pi (π)is roughly equal to 3.14.

Formula to Calculate Revolutions per Mile

Once you have calculated the circumference of the tire, it’s probable enough to find out the revolutions per mile of the tire by using the mentioned formula, including;

Revolutions per mile of the tire = 63,360 ÷ circumference of the tire

The result of revolutions per mile of the tire is received in inches with the calculation of the appropriate tire size finder.

Hence, be smart enough to find the accurate tire size by applying an appropriate calculation through the tire size finder for your car while buying a new one or replacing the old one. With this, you will also be provided with an assessment of alternative tires that are compatible enough with the perfect tire size.