In the tire comparison table above, you can see a detailed calculation of the size difference between 225/65 R17 and 245/60 R18 tire. The calculation results are presented in the form of visual infographics, on which tire with size 225/65 R17 is on top, and tire with size 245/60 R18 below. Both in the table and in the graph, the tires are 235/60-R18 tires are 0.93 inches (23.5 mm) larger in diameter than 235/55-R18 tires and the speedometer difference is 3.2%. 215/60-R17 tires are 0.09 inches (2.4 mm) smaller in diameter than 235/50-R18 tires and the speedometer difference is 0.4% 215/60 r17 -3.6% 215/65 r17 -0.7% 225/60 r17 -2% 225/65 r17 +1.1% 235/55 r17 -3.6% 235/60 r17 -0.3% 235/65 r17 +2.9% 245/55 r17 -2.1% 255/55 r17 -0.6% 255/60 r17 +3.1 In the tire comparison table above, you can see a detailed calculation of the size difference between 235/55 R18 and 235/50 R18 tire. The calculation results are presented in the form of visual infographics, on which tire with size 235/55 R18 is on top, and tire with size 235/50 R18 below. Both in the table and in the graph, the tires are The first number 235 is the tire width in millimeters. The 2nd number 65 is used to calculate the sidewall height or "aspect ratio", by percentage. So, the sidewall height of a 235/65 R 18 tire is 60% of 235 = 192. The 3rd number 18 (generally preceded by an "R") is Rim Diameter in inches. .

235 60 r18 vs 235 65 r17