Tyre Sidewall Measurement Guide

On the sidewall of your tyre you will see 4 numbers (one with an R in front of it) and a letter. An example of this would be 285/75R16 116Q. To explain what each of these numbers and letters mean we have created this guide to explain each one:

Marking Explanation
285 Width of the tyre in millimetres. On some tyres this number could be 30 or 35 for example, this is the height in inches (they are still listed under width on our dropdown boxes for ease of use).
75 Profile – Also known as the aspect ratio. This number is the tyre’s height as a percentage of the width. In this case it would be 75% of 285 (213.75mm). In instances where the tyre’s first number is in inches (for example 30/7.50R15) then this number (7.50 in the example) is the tyre’s width in inches (they are still listed under profile on our dropdown boxes for ease of use).
R This stands for ‘Radial’ as in ‘Radial Construction‘.
16 Diameter – The tyre’s inner rim measurement in inches.
116 This is the tyre’s Load Rating. In this example this tyre could take 1250kg of weight.
Q The tyre’s Speed Rating. This shows the maximum speed when at full load which, in this example, would equate to 99mph/160kmph.

If you have any questions regarding your tyre’s sidewall measurements, please feel free to ask one of our specialists by either calling us on 01582 585 845 or filling out our contact form and asking about sidewall measurements.