225/35 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 (225mm), which means the sidewall height has 78.75 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 265/35 R19
(2098.9 mm), 195/65 R16
(2073.14 mm), 265/45 R18
(2185.61 mm), 205/40 R17
(1871.76 mm), 265/65 R18
(2518.61 mm), 205/55 R16
(1985.17 mm), 275/35 R18
(2041.09 mm).