145/70 R12 doesn't belong to the most popular dimensions for summer 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 - 70 is height of the tyre, which is calculated as 70% of the tyre width (145mm), which means the sidewall height has 101.5 mm. The wheel diameter is R12, which means it fits to a 12 inch/304.8mm diameter wheel. The total circumference of the tyre is mm, which is very similar to 165/65 R14
(1791.02 mm), 245/45 R20
(2288.65 mm), 175/60 R14
(1776.88 mm), 245/70 R17
(2434.11 mm), 175/80 R14
(1996.8 mm), 255/40 R18
(2077.22 mm), 185/60 R14
(1814.58 mm).
