195/35 R20 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 - 35 is height of the tyre, which is calculated as 35% of the tyre width (195mm), which means the sidewall height has 68.25 mm. The wheel diameter is R20, which means it fits to a 20 inch/508mm diameter wheel. The total circumference of the tyre is mm, which is very similar to 205/55 R16(1985.17 mm), 275/30 R21(2194.09 mm), 205/75 R16(2242.78 mm), 275/40 R21(2366.88 mm), 215/45 R18(2044.23 mm), 275/55 R19(2466.46 mm), 215/65 R15(2075.02 mm).