225/55R18 is a tire size:
225 = tire width in millimeters
55 = aspect ratio (sidewall height is 55% of the width)
R = radial construction
18 = wheel/rim diameter in inches
This size is commonly found on many crossovers, SUVs, and sedans.
What would you like to know about this size?
Recommended tire options
Price range
Compatible vehicle models
Winter vs. all-season tires
Overall diameter or speedometer impact compared with another size