GarageCalc What 225/75R16 means
225 is the section width in millimeters (8.9 in). 75 is the aspect ratio: the sidewall is 75 percent of the width, so 225 × 0.75 = 169 mm (6.6 in). R is radial construction, and 16 is the wheel diameter in inches (406 mm). Stack two sidewalls on the wheel and you get the overall diameter: 406 + 2 × 169 = 744 mm, or 29.3 in.
A full marking adds a load index and speed rating after the size, for example 225/75R16 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 225/75R16
Going up one wheel size, the closest match is 245/65R17 at +0.9% diameter with a 159 mm sidewall instead of 169 mm. Going down one size, 235/75R15 is -1.4% with a taller 176 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 225/75R16
Typical factory fitments include Jeep Wrangler JK Sport (2007-2018). Tire size changes with trim and wheel option, so confirm on the door-jamb placard before buying.
Frequently asked questions
How tall is a 225/75R16 tire?
29.3 inches (744 mm) in overall diameter: the 16-inch wheel (406 mm) plus two 169 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 225/75R16 in inches?
29.3 x 8.9 R16: 29.3 inches tall, 8.9 inches wide, on a 16-inch wheel. The sidewall is 6.6 inches and the circumference is 92.0 inches, so the tire turns 689 times per mile.
What tire sizes are equivalent to 225/75R16?
Within 3 percent of the same diameter on the same 16-inch wheel: 245/70R16 (+0.7%), 235/70R16 (-1.1%), 215/75R16 (-2.0%); on a 17-inch wheel: 245/65R17 (+0.9%), 235/65R17 (-0.9%); on a 15-inch wheel: 235/75R15 (-1.4%). The percentage is the diameter change, which is also your speedometer error.
Can I use 235/70R16 instead of 225/75R16?
Dimensionally yes: 235/70R16 is 1.1% shorter (-9 mm) and 10 mm wider, and at a true 60 mph the speedometer would read 60.7 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.