215/45 R17 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 - 45 is height of the tyre, which is calculated as 45% of the tyre width (215mm), which means the sidewall height has 96.75 mm. The wheel diameter is R17, which means it fits to a 17 inch/431.8mm diameter wheel. The total circumference of the tyre is mm, which is very similar to 245/70 R16(2354.31 mm), 175/70 R14(1886.84 mm), 255/40 R17(1997.42 mm), 185/55 R15(1836.26 mm), 255/45 R20(2316.92 mm), 185/75 R14(1988.94 mm), 255/65 R16(2318.18 mm). You can find 215/45 R17 on 38 car models - mainly Toyota, Opel, Alfa Romeo, Subaru, Ford.