GarageCalc What 295/70R17 means
295 is the section width in millimeters (11.6 in). 70 is the aspect ratio: the sidewall is 70 percent of the width, so 295 × 0.70 = 207 mm (8.1 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 × 207 = 845 mm, or 33.3 in.
A full marking adds a load index and speed rating after the size, for example 295/70R17 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 295/70R17
Going up one wheel size, the closest match is 275/70R18 at -0.3% diameter with a 193 mm sidewall instead of 207 mm. Going down one size, 285/75R16 is -1.3% with a taller 214 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 295/70R17 tire?
33.3 inches (845 mm) in overall diameter: the 17-inch wheel (432 mm) plus two 207 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 295/70R17 in inches?
33.3 x 11.6 R17: 33.3 inches tall, 11.6 inches wide, on a 17-inch wheel. The sidewall is 8.1 inches and the circumference is 104.5 inches, so the tire turns 606 times per mile.
What tire sizes are equivalent to 295/70R17?
Within 3 percent of the same diameter on the same 17-inch wheel: 285/70R17 (-1.7%), 285/75R17 (+1.7%); on an 18-inch wheel: 275/70R18 (-0.3%), 285/70R18 (+1.3%); on a 16-inch wheel: 285/75R16 (-1.3%), 305/70R16 (-1.3%). The percentage is the diameter change, which is also your speedometer error.