225/40 R20 - Best summer tyres 2025 - market overview, tests, reviews

225/40 R20 doesn't belong to the most popular dimensions for summer tyres - there are 1 tyre models available, which can be compared to 155/60 R15, 170/60 R17, 160/60 R14. Let's break down the sizing - 40 is height of the tyre, which is calculated as 40% of the tyre width (225mm), which means the sidewall height has 90 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is 2161.42 mm, which is very similar to 235/60 R16(2162.67 mm), 295/35 R19(2164.87 mm), 255/45 R18(2157.33 mm), 255/40 R19(2157.02 mm), 255/35 R20(2156.7 mm), 215/60 R17(2167.07 mm), 215/65 R16(2154.82 mm). There are multiple speed indexes available for summer tyres in 225/40 R20: V(240km/h), Y(300km/h). The same goes for weight indexes: 94.