What does the 255 mean on a tire?
Joseph Russell
Updated on June 03, 2026
255 (Tire Width): The tire width is 255 millimeters from sidewall to sidewall (just over ten inches). 45 (Aspect Ratio): The tire's sidewall is 45% of the tire's width, which means the sidewall is about 114 millimeters or just over 4 inches.