Dunlop Grandtrek ST20 225/65 R18

Dunlop Grandtrek ST20 is a summer tyre made in total of 11 sizes, ranging from R13 to R13 - this particular dimension is R18, which means it fits to a 18 inch/457.2mm diameter wheel. 225/65 R18 is 10mm wider than the narrowest dimension (215) and 0mm narrower than the widest one (225). This tyre profile of 65 means the sidewall height of the tyre is 65% of the tyre width (225mm), which results in 146.25mm sidewall height.