255/65 R19 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 - 65 is height of the tyre, which is calculated as 65% of the tyre width (255mm), which means the sidewall height has 165.75 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 275/65 R18(2559.46 mm), 215/65 R17(2234.61 mm), 285/35 R20(2222.68 mm), 225/35 R19(2010.93 mm), 285/45 R21(2481.54 mm), 225/50 R17(2063.4 mm), 295/30 R22(2311.58 mm).