GarageCalc What 235/60R15 means
235 is the section width in millimeters (9.3 in). 60 is the aspect ratio: the sidewall is 60 percent of the width, so 235 × 0.60 = 141 mm (5.6 in). R is radial construction, and 15 is the wheel diameter in inches (381 mm). Stack two sidewalls on the wheel and you get the overall diameter: 381 + 2 × 141 = 663 mm, or 26.1 in.
A full marking adds a load index and speed rating after the size, for example 235/60R15 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 235/60R15
Going up one wheel size, the closest match is 215/60R16 at +0.2% diameter with a 129 mm sidewall instead of 141 mm. Going down one size, 215/70R14 is -1.0% with a taller 151 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.
Frequently asked questions
How tall is a 235/60R15 tire?
26.1 inches (663 mm) in overall diameter: the 15-inch wheel (381 mm) plus two 141 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 235/60R15 in inches?
26.1 x 9.3 R15: 26.1 inches tall, 9.3 inches wide, on a 15-inch wheel. The sidewall is 5.6 inches and the circumference is 82.0 inches, so the tire turns 773 times per mile.
What tire sizes are equivalent to 235/60R15?
Within 3 percent of the same diameter on the same 15-inch wheel: 215/65R15 (-0.4%), 225/60R15 (-1.8%), 215/70R15 (+2.9%); on a 16-inch wheel: 215/60R16 (+0.2%), 225/55R16 (-1.4%); on a 14-inch wheel: 215/70R14 (-1.0%). The percentage is the diameter change, which is also your speedometer error.