GarageCalc What 165/70R14 means
165 is the section width in millimeters (6.5 in). 70 is the aspect ratio: the sidewall is 70 percent of the width, so 165 × 0.70 = 116 mm (4.5 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 × 116 = 587 mm, or 23.1 in.
A full marking adds a load index and speed rating after the size, for example 165/70R14 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 165/70R14
Going up one wheel size, the closest match is 185/55R15 at -0.4% diameter with a 102 mm sidewall instead of 116 mm. Going down one size, 185/70R13 is +0.4% with a taller 130 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 165/70R14 tire?
23.1 inches (587 mm) in overall diameter: the 14-inch wheel (356 mm) plus two 116 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 165/70R14 in inches?
23.1 x 6.5 R14: 23.1 inches tall, 6.5 inches wide, on a 14-inch wheel. The sidewall is 4.5 inches and the circumference is 72.6 inches, so the tire turns 873 times per mile.
What tire sizes are equivalent to 165/70R14?
Within 3 percent of the same diameter on the same 14-inch wheel: 175/65R14 (-0.6%), 185/60R14 (-1.5%), 185/65R14 (+1.6%); on a 15-inch wheel: 185/55R15 (-0.4%), 175/60R15 (+0.8%); on a 13-inch wheel: 185/70R13 (+0.4%), 165/80R13 (+1.3%). The percentage is the diameter change, which is also your speedometer error.
Can I use 175/65R14 instead of 165/70R14?
Dimensionally yes: 175/65R14 is 0.6% shorter (-4 mm) and 10 mm wider, and at a true 60 mph the speedometer would read 60.4 mph. The extra width needs about 0.20 in of clearance on each side of the tire and a rim width that suits 175 mm.