225/60 R15 doesn't belong to the most popular dimensions for summer tyres - there are 7 tyre models available, which can be compared to 155/60 R15, 160/60 R18, 165/60 R14. Let's break down the sizing - 60 is height of the tyre, which is calculated as 60% of the tyre width (225mm), which means the sidewall height has 135 mm. The wheel diameter is R15, which means it fits to a 15 inch/381mm diameter wheel. The total circumference of the tyre is 2045.18 mm, which is very similar to 215/45 R18(2044.23 mm), 285/25 R20(2043.61 mm), 185/80 R14(2047.06 mm), 200/55 R17(2047.69 mm), 245/45 R17(2049.26 mm), 275/35 R18(2041.09 mm), 205/60 R16(2049.58 mm). There are multiple speed indexes available for summer tyres in 225/60 R15: S(180km/h), V(240km/h), W(270km/h), Y(300km/h). The same goes for weight indexes: 95, 96.