305/30 R19 doesn't belong to the most popular dimensions for winter 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 - 30 is height of the tyre, which is calculated as 30% of the tyre width (305mm), which means the sidewall height has 91.5 mm. The wheel diameter is R19, which means it fits to a 19 inch/482.6mm diameter wheel. The total circumference of the tyre is mm, which is very similar to 245/75 R16
(2431.28 mm), 180/55 R17
(1978.58 mm), 255/40 R19
(2157.02 mm), 185/60 R15
(1894.38 mm), 255/50 R20
(2397.04 mm), 190/50 R17
(1953.44 mm), 255/70 R15
(2318.5 mm).
