GarageCalc What 225/60R18 means
225 is the section width in millimeters (8.9 in). 60 is the aspect ratio: the sidewall is 60 percent of the width, so 225 × 0.60 = 135 mm (5.3 in). R is radial construction, and 18 is the wheel diameter in inches (457 mm). Stack two sidewalls on the wheel and you get the overall diameter: 457 + 2 × 135 = 727 mm, or 28.6 in.
A full marking adds a load index and speed rating after the size, for example 225/60R18 91V. Those two codes set how much weight and speed the tire is certified for; look them up in the load index chart and the speed rating chart.
Plus and minus sizing from 225/60R18
Going up one wheel size, the closest match is 245/50R19 at +0.1% diameter with a 123 mm sidewall instead of 135 mm. Going down one size, 225/65R17 is -0.4% with a taller 146 mm sidewall for more comfort and pothole margin. Anything inside 3 percent keeps the speedometer, ABS and gearing effectively stock; the comparison calculator shows the full speedometer table for any pair.
Which cars come with 225/60R18
Typical factory fitments include Toyota RAV4 XLE Premium and Limited (2019 on) and Lexus NX (2015-2021). Tire size changes with trim and wheel option, so confirm on the door-jamb placard before buying.
Frequently asked questions
How tall is a 225/60R18 tire?
28.6 inches (727 mm) in overall diameter: the 18-inch wheel (457 mm) plus two 135 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 225/60R18 in inches?
28.6 x 8.9 R18: 28.6 inches tall, 8.9 inches wide, on an 18-inch wheel. The sidewall is 5.3 inches and the circumference is 89.9 inches, so the tire turns 704 times per mile.
What tire sizes are equivalent to 225/60R18?
Within 3 percent of the same diameter on the same 18-inch wheel: 245/55R18 (-0.1%), 235/55R18 (-1.6%), 235/60R18 (+1.7%); on a 19-inch wheel: 245/50R19 (+0.1%), 225/55R19 (+0.4%); on a 17-inch wheel: 225/65R17 (-0.4%), 235/65R17 (+1.4%). The percentage is the diameter change, which is also your speedometer error.
Can I use 235/55R18 instead of 225/60R18?
Dimensionally yes: 235/55R18 is 1.6% shorter (-12 mm) and 10 mm wider, and at a true 60 mph the speedometer would read 61.0 mph. The extra width needs about 0.20 in of clearance on each side of the tire and a rim width that suits 235 mm.