345/25 R20 doesn't belong to the most popular dimensions for summer tyres - there are 2 tyre models available, which can be compared to
155/60 R15,
170/60 R17,
160/60 R14. Let's break down the sizing - 25 is height of the tyre, which is calculated as 25% of the tyre width (345mm), which means the sidewall height has 86.25 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is 2137.85 mm, which is very similar to 245/35 R20
(2134.71 mm), 195/70 R16
(2134.4 mm), 225/55 R17
(2134.08 mm), 285/30 R20
(2133.14 mm), 215/70 R15
(2142.57 mm), 285/35 R19
(2142.88 mm), 225/50 R18
(2143.19 mm). There are multiple speed indexes available for summer tyres in 345/25 R20: Y
(300km/h). The same goes for weight indexes: 100, 104.
