Tire Diameter Calculator

Tire Diameter Calculator

Tire Width (mm):
Aspect Ratio (Tire Series):
Wheel Size (inches):
Thank us with a "Like":
Need multiple calculators?
We offer bulk pricing on orders over 10 calculators. Contact Us
Not what you're looking for?
Get your own custom-built calculator. Contact Us

Get this calculator for your site:

Calculations - 100/month. Required link back.


Calculations - unlimited. Customizable. No link.

Tire Diameter Formula:

Tire Diameter = 2*(Tire Width/25.4)*(Aspect Ratio/100)-(Wheel Size*-1)

Tire Diameter Definition

The Tire Diameter Calculator will instantly calculate the diameter of a tire if you enter in the tire width (in millimeters), the tire aspect ratio (also known as the tire series), and the wheel size (in inches).

It is generally recommended that when you want to change the size of the tires on your vehicle that you stay within approximately 3% of the diameter and height of the current tires on your vehicle so that the brakes on the vehicle will work properly. Also keep in mind that there are often very slight variations in tire sizes between different brands and also between used tires and tires that have differing amount of wear.

How to Calculate Tire Diameter

Let's be honest - sometimes the best tire diameter calculator is the one that is easy to use and doesn't require us to even know what the tire diameter formula is in the first place! But if you want to know the exact formula for calculating tire diameter then please check out the "Formula" box above.

Add a Free Tire Diameter Calculator Widget to Your Site!

You can get a free online tire diameter calculator for your website and you don't even have to download the tire diameter calculator - you can just copy and paste! The tire diameter calculator exactly as you see it above is 100% free for you to use. If you want to customize the colors, size, and more to better fit your site, then pricing starts at just $29.99 for a one time purchase. Click the "Customize" button above to learn more!