235/30 R20 doesn't belong to the most popular dimensions for winter 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 - 30 is height of the tyre, which is calculated as 30% of the tyre width (235mm), which means the sidewall height has 70.5 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is 2038.89 mm, which is very similar to 160/60 R18
(2039.52 mm), 275/35 R18
(2041.09 mm), 180/60 R17
(2035.12 mm), 275/30 R19
(2034.5 mm), 205/65 R15
(2034.18 mm), 285/25 R20
(2043.61 mm), 215/45 R18
(2044.23 mm). There are multiple speed indexes available for winter tyres in 235/30 R20: V
(240km/h). The same goes for weight indexes: 88.
