275/45 R21 - Best tyres 2026 - market overview, tests, reviews

275/45 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 (275mm), which means the sidewall height has 123.75 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 215/40 R16(1817.1 mm), 275/45 R19(2293.68 mm), 215/55 R16(2019.73 mm), 285/25 R20(2043.61 mm), 215/70 R15(2142.57 mm), 285/35 R22(2382.27 mm), 225/35 R20(2090.73 mm).