285/45 R21 - Best tyres 2025 - market overview, tests, reviews

285/45 R21 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 (285mm), which means the sidewall height has 128.25 mm. The wheel diameter is R21, which means it fits to a 21 inch/533.4mm diameter wheel. The total circumference of the tyre is mm, which is very similar to 295/25 R20(2059.31 mm), 225/55 R17(2134.08 mm), 295/40 R20(2337.34 mm), 225/65 R17(2275.46 mm), 315/40 R21(2467.41 mm), 235/40 R18(2026.96 mm), 235/50 R19(2254.41 mm).