160/60 R18 doesn't belong to the most popular dimensions for tyres - there are tyre models available, which can be compared to 325/30 R21, 155/60 R15, 155/65 R13. Let's break down the sizing - 60 is height of the tyre, which is calculated as 60% of the tyre width (160mm), which means the sidewall height has 96 mm. The wheel diameter is R18, which means it fits to a 18 inch/457.2mm diameter wheel. The total circumference of the tyre is mm, which is very similar to 225/35 R20(2090.73 mm), 285/50 R20(2491.28 mm), 225/50 R18(2143.19 mm), 295/35 R19(2164.87 mm), 225/60 R18(2284.57 mm), 305/30 R20(2170.84 mm), 235/35 R20(2112.72 mm).