» Useful » How to calculate the height of a tire profile?
How to calculate tire profile height?
The height of the tire profile in its pure form is not indicated on the tire itself. For example, consider a Next read truck tire (remanufactured by Goodyear) marked 315/80R22.5. From the size you can see that the fit diameter (rim size) is 22.5 inches, and the width of the tire profile is 315 mm. Next, a certain number 80 appears, which, as we wrote earlier, indicates attitude profile height (SH) to profile width (SD), expressed as a percentage.
Thus, to calculate the profile height (SH) of a given tire, you need to:
SH = SD x (Profile height to width ratio / 100%)
SH = 315 x (80/100) = 252 mm
Thus, to simplify calculations in the field, we pre-divide the profile height to width ratio by 100, and then multiply the profile width.
In conclusion, we note that the smaller the numerical value of the ratio of the profile height to its width, the smaller the profile height at constant profile width. For example, for size 315/70, the profile height will be 220.5 mm, and for size 315/60 it is 189 mm. In any case, the profile height cannot exceed its width.
What is a tire calculator for?
With this tire calculator, you can easily calculate how the outer dimensions of the wheel, ride height (clearance), speedometer readings and other characteristics will change when you install tires with a different size on your car.
Old tire size
Width
Height
Diameter
New tire size
Width
Select 5.0 5.5 6.0 6.5 7.0 7.5.5 8.5 9.5 10.5 11.5 12.0 12.5 13.0 13.5 14.5 125 135 145 155 175 175 295 195 205 215 225 235 295 355 335 335 335 355 365
Height
Select 25 27 30 31 32 33 34 35 38 38.5 40 45 50 55 60 65 70 75 80 85 90
Diameter
Select 12 13 14 15 16 16.5 17 17.5 18 19 20 21 22 23 24 25 26 28 30 32
First enter the standard size installed on your car, and then the one you want to install.
The difference between the speedometer and the actual speed depends on the speed of the car, the higher the speed, the greater the difference
| External dimensions | old | New | Difference | ||
|---|---|---|---|---|---|
| Tire width, mm (A) | 0 | 0 | 0 | ||
| Profile height, mm (B) | 0 | 0 | 0 | ||
| Disc diameter, mm (C) | 0 | 0 | 0 | ||
| External diameter, mm (D) | 0 | 0 | 0 | ||
| Change in ground clearance, mm | 0 |
The site of the online store contains a convenient tire calculator that makes it easy to calculate changes in wheel parameters when switching to another tire size. With this online tool, you can calculate external wheel measurements, ground clearance (ride height), calculate speedometer readings and other characteristics.
With the onset of the new season, every responsible car owner considers it necessary to change tires in accordance with the season. The best option would be to install tires of the size recommended by the automaker for a particular car brand. In cases where this is not possible, deviations in diameter in the 2% range are allowed.
Replacing tires requires a serious approach. When choosing new tires and wheels, it is necessary to take into account such indicators as:
- tire width,
- profile height,
- wheel inner diameter,
- valid speed indices.
Incorrectly selected tires can cause malfunctions in the car's electronics, increase fuel consumption, worsen driving comfort, and also cause problems during a vehicle inspection at the traffic police.
How to calculate tires?
To select the tires of the required size, you need to use the tire calculator, which determines the theoretical dimensions. All measurements are in millimeters and speed is in km/h. To make a calculation, you should enter the parameters of the tires of your car in the appropriate line. Then enter the dimensions of the new tire and rim to be installed. After specifying all the parameters in the table below, information will appear on changes in the tire width and profile height, inner and outer diameters, and the difference in speeds (real and according to the speedometer).
What to look for when choosing a tire
- Installing tires and wheels of non-standard size can lead to damage to the tire itself, damage to the wheel and reduce the performance of the car. When choosing tires, it is better to rely on the recommendations of the automaker.
- If the diameter of the wheel disc is larger, then in this case the load on the suspension may increase. To maintain the same diameter of the outer wheel, the height of the profile should be reduced.
- If you choose tires with a greatly increased profile, you need to be prepared for a loss in the quality of car handling. The tire can rub against the body and suspension, causing rapid wear.
- Even with the slightest difference between the indicators on the speedometer and in reality, the error can increase many times with an increase in speed, which makes driving unsafe.
- Narrow or too wide rims can cause tire deformation. This, in turn, will lead to premature wear and deterioration of performance.
Car owners use a tire calculator to select tires and rims of the right size. All calculations are done online. The user does not have to deal with lengthy, incomprehensible calculations. The application is multifunctional, since the motorist will be able to understand how to change the dimensions of the wheel, taking into account changes in the size of tires and wheels. Consider the features of using the service.
Tire calculator functionality
To help with the selection of tires suitable for a particular car in terms of size and characteristics, the tire selection calculator can. Vehicle owners resort to the services of the service when it is time to replace the tires and wheels on the vehicle. In order not to waste time on meaningless "changing shoes", checks, use the proposed online service. Tire calculator features:
- you can calculate the size of tires;
- the service provides different parameters - wheel diameters, changes in the height of the clearance between the road and the car (clearance), track expansion;
- help in converting inches to millimeters or vice versa, using the American and European size charts.
The tire calculator has been designed to speed up the selection of tires, making the procedure much easier. Since every owner of a car faced the difficulties of choosing, online calculators very quickly gained popularity among users.
How to use the tire calculator
There are several tips to help you use the tire size calculator for its intended purpose. The step-by-step instruction consists of the following steps:
- In the form you will need to enter the size of the tires installed on the car, as well as those that you would like to install.
- The user will see a special table with the results of calculations. From this data, it will be possible to find out which tires are needed for a particular vehicle.
- After selecting tires, you can proceed to the calculation of the size of the disks. Here you will need to set the exact data - the maximum / minimum width of the disk installed on the car. All calculations will be performed automatically.
- If you need to convert inches to millimeters, you can use the online converter. This action will allow you to find analogues with American sizes and with European ones. Comparison through the tire calculator will be as accurate as possible, since all the necessary information has been entered into the online service database.
The general selection procedure is very simple, but the owner of the car will definitely need to enter the initial data. The parameters should be as accurate as possible so that there are no errors or inaccuracies in subsequent results.
You can use this service on our website. The program is freely available, anyone can make calculations in a few minutes. To simplify the process of use, it is worth using the instructions given.
During the selection of new wheels for a car, the question often arises, should I put wheels larger or smaller, or in order to improve the appearance of the car or reduce the cost of buying tires and wheels. But the most important question arises, will the wheels fit my car and how will its characteristics change. You can understand whether the wheels will fit on the gas tank cap or the side stand of the car (photo 1). Or find your car in our directory of applicability of discs to cars, and see the tires recommended by the factory. But it often happens that you can put other tires that are not officially approved by the factory.
In this case, the main thing is to understand how the speedometer will change, i.e. the speed of the machine, as the outer radius of the wheel will change. The clearance (ground clearance) will also change. It is not recommended to go beyond the values of factory tires by more than 2-3%. The handling and behavior of the car, the consumption of gasoline and the actual speed of the car may change.
Tire calculator - size comparison
Our tire calculator will show you visual differences in tire diameter, profile, radius, ground clearance and width. Dashed lines show the difference in size. At the top, you can see a visual representation of the old tire (original size), and at the bottom, a visualization of the new tire. Just as you noticed, the tire can be seen in lateral and frontal projection. You can copy the URL of the page and show it to other people and they will see the same comparison as you see.
But how to understand all these values \u200b\u200band the difference in%? To do this, we created a tire calculator, it will help you understand the change in all the necessary characteristics and show the difference in% between the old and new tires, and even visually display how the wheel of the old and new sizes will look like. You just need to enter the tire width, profile and wheel radius. Usually they are displayed in this form - 195 \ 65 R15 (photo 2).
How to use the online tire calculator?
Using our online tire calculator is very easy. In the upper left corner of the site, there are fields for choosing a tire size. In the top row, you need to indicate the size of your original factory tire (or the tires that are currently installed on your car). These values are written on the tire profile (side surface). In the first list, you need to select the tire width - it is indicated in millimeters. The second list is the percentage of profile height to tire width. The third list is the disc diameter in inches (commonly referred to as the radius).
In the bottom row you need to specify the size of the new tires. Tires that you are going to install on a car or have already bought. Then click "Calculate". Our tire calculator will calculate the differences between the old and new tires and display them in a table and a picture. Namely: diameter, width, circumference, tire profile height, number of revolutions per kilometer and change in car clearance. The first columns of the table will show the parameters for old and new tyres, the following columns will show the difference in mm and the percentage difference between them.
There is a speedometer at the bottom of the tire calculator to visually compare the speed of the old and new tires. Under the speedometer, you can speed up and slow down and see the change in speed difference between the old and new tires.
Be careful!
Be careful on the road and follow the manufacturer's recommendations. The reverse side of installing non-standard tire sizes is the risk of losing insurance in case of an accident, not passing the state technical inspection of the car, since setting tires that are not approved by the factory is considered a change in the design of the vehicle.
Using the tire calculator, you can easily calculate how the outer dimensions of the wheel, ride height (clearance), speedometer readings and other characteristics will change when you install tires with a different size on your car. The calculator calculates all tire sizes in millimeters, and the vehicle speed in km / h.
Also, the calculator will help you calculate the required rim width for a specific tire size.
How to use the tire calculator:
First enter the standard size installed on your car, and then the one you want to install and click "calculate". The table on the right will show the results of the calculator's calculations.
Detailed information about tire marking in the section: tire marking.
We recommend that you install only the factory tire sizes that are listed in the owner's manual for your machine. Installation of non-standard sizes may void your dealer's warranty and may affect vehicle performance and handling.
Tire calculator for European tires
Old size:
new size:
145 155 165 175 185 195 205 215 225 235 245 255 265 275 285 295 305 315 325
/ 25 30 35 40 45 50 55 60 65 70 75 80 85
12 13 14 15 16 17 18 19 20 21 22 23 24
Found in catalogue:
175/70R13-
175/70R13-
When recalculating tire sizes on a calculator, it should be borne in mind that:
With an increase in the diameter of the rim (and, as a result, a decrease in the height of the tire profile so that the outer diameter of the wheel remains unchanged), the load on the car suspension increases, as well as comfort worsens (the car will become noticeably stiffer).
With an excessive increase in the tire profile, the car becomes a “roll”, it is worse controlled, and at critical values \u200b\u200bof the profile height, the tire may begin to cling to body parts and suspension of the car, which will subsequently lead to its destruction.
