305/25 R20 doesn't belong to the most popular dimensions for winter tyres - there are 0 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 (305mm), which means the sidewall height has 76.25 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is 2075.02 mm, which is very similar to 215/65 R15
(2075.02 mm), 255/30 R20
(2076.59 mm), 195/65 R16
(2073.14 mm), 255/35 R19
(2076.91 mm), 255/40 R18
(2077.22 mm), 225/45 R18
(2072.51 mm), 255/45 R17
(2077.54 mm).
