GarageCalc What 215/50R17 means
215 is the section width in millimeters (8.5 in). 50 is the aspect ratio: the sidewall is 50 percent of the width, so 215 × 0.50 = 108 mm (4.2 in). R is radial construction, and 17 is the wheel diameter in inches (432 mm). Stack two sidewalls on the wheel and you get the overall diameter: 432 + 2 × 108 = 647 mm, or 25.5 in.
A full marking adds a load index and speed rating after the size, for example 215/50R17 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 215/50R17
Going up one wheel size, the closest match is 235/40R18 at -0.2% diameter with a 94 mm sidewall instead of 108 mm. Going down one size, 215/55R16 is -0.6% with a taller 118 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 215/50R17
Typical factory fitments include Honda Civic EX and Touring (2016-2021). Tire size changes with trim and wheel option, so confirm on the door-jamb placard before buying.
Frequently asked questions
How tall is a 215/50R17 tire?
25.5 inches (647 mm) in overall diameter: the 17-inch wheel (432 mm) plus two 108 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 215/50R17 in inches?
25.5 x 8.5 R17: 25.5 inches tall, 8.5 inches wide, on a 17-inch wheel. The sidewall is 4.2 inches and the circumference is 80.0 inches, so the tire turns 792 times per mile.
What tire sizes are equivalent to 215/50R17?
Within 3 percent of the same diameter on the same 17-inch wheel: 235/45R17 (-0.5%), 205/50R17 (-1.5%), 225/50R17 (+1.5%); on an 18-inch wheel: 235/40R18 (-0.2%), 215/45R18 (+0.6%); on a 16-inch wheel: 215/55R16 (-0.6%), 205/60R16 (+0.9%). The percentage is the diameter change, which is also your speedometer error.
Can I use 225/50R17 instead of 215/50R17?
Dimensionally yes: 225/50R17 is 1.5% taller (+10 mm) and 10 mm wider, and at a true 60 mph the speedometer would read 59.1 mph. The extra width needs about 0.20 in of clearance on each side of the tire and a rim width that suits 225 mm.