225/40 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 - 40 is height of the tyre, which is calculated as 40% of the tyre width (225mm), which means the sidewall height has 90 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 235/45 R17(2020.99 mm), 235/55 R18(2248.44 mm), 235/65 R18(2396.09 mm), 155/70 R19(2197.86 mm), 245/35 R21(2214.51 mm), 165/60 R15(1818.98 mm), 245/45 R19(2208.85 mm). You can find 225/40 R19 on 8 car models - mainly Mercedes-Benz, Fiat, Hyundai, Jaguar, Kia.