10 answers
Automotive - tire size
Direct answers to every common question in this cluster. Each page has the computed value, the formula, and a live converter.
Quick reference
A tire size like 225/45R17 means: 225 mm tread width, 45% aspect ratio (sidewall is 45% of width = 101 mm), R for radial construction, 17-inch wheel diameter. Total tire diameter: 17 × 25.4 + 2 × 101 = 634 mm. Different sizes with the same diameter are 'plus-sized' if the wheel is bigger.
Every answer in this topic
- What is the difference between 185/60R15 and 195/50R15 tires?
- What is the difference between 195/55R16 and 205/50R17 tires?
- What is the difference between 205/55R16 and 225/45R17 tires?
- What is the difference between 215/45R17 and 225/40R18 tires?
- What is the difference between 225/40R18 and 235/35R19 tires?
- What is the difference between 225/45R17 and 235/40R18 tires?
- What is the difference between 235/35R19 and 245/35R19 tires?
- What is the difference between 245/45R18 and 255/40R19 tires?
- What is the difference between 255/40R18 and 275/35R18 tires?
- What is the difference between 265/35R18 and 285/30R19 tires?