GarageCalc What 175/70R14 means
175 is the section width in millimeters (6.9 in). 70 is the aspect ratio: the sidewall is 70 percent of the width, so 175 × 0.70 = 123 mm (4.8 in). R is radial construction, and 14 is the wheel diameter in inches (356 mm). Stack two sidewalls on the wheel and you get the overall diameter: 356 + 2 × 123 = 601 mm, or 23.6 in.
A full marking adds a load index and speed rating after the size, for example 175/70R14 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 175/70R14
Going up one wheel size, the closest match is 185/60R15 at +0.4% diameter with a 111 mm sidewall instead of 123 mm. Going down one size, 165/80R13 is -1.1% with a taller 132 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 175/70R14 tire?
23.6 inches (601 mm) in overall diameter: the 14-inch wheel (356 mm) plus two 123 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 175/70R14 in inches?
23.6 x 6.9 R14: 23.6 inches tall, 6.9 inches wide, on a 14-inch wheel. The sidewall is 4.8 inches and the circumference is 74.3 inches, so the tire turns 853 times per mile.
What tire sizes are equivalent to 175/70R14?
Within 3 percent of the same diameter on the same 14-inch wheel: 185/65R14 (-0.7%), 195/65R14 (+1.4%), 195/60R14 (-1.8%); on a 15-inch wheel: 185/60R15 (+0.4%), 165/65R15 (-0.8%); on a 13-inch wheel: 165/80R13 (-1.1%), 185/70R13 (-1.9%). The percentage is the diameter change, which is also your speedometer error.
Can I use 185/65R14 instead of 175/70R14?
Dimensionally yes: 185/65R14 is 0.7% shorter (-5 mm) and 10 mm wider, and at a true 60 mph the speedometer would read 60.5 mph. The extra width needs about 0.20 in of clearance on each side of the tire and a rim width that suits 185 mm.