GarageCalc What 205/70R14 means
205 is the section width in millimeters (8.1 in). 70 is the aspect ratio: the sidewall is 70 percent of the width, so 205 × 0.70 = 144 mm (5.6 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 × 144 = 643 mm, or 25.3 in.
A full marking adds a load index and speed rating after the size, for example 205/70R14 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 205/70R14
Going up one wheel size, the closest match is 215/60R15 at -0.6% diameter with a 129 mm sidewall instead of 144 mm. No common 13-inch size stays within 3 percent either. 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 205/70R14 tire?
25.3 inches (643 mm) in overall diameter: the 14-inch wheel (356 mm) plus two 144 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 205/70R14 in inches?
25.3 x 8.1 R14: 25.3 inches tall, 8.1 inches wide, on a 14-inch wheel. The sidewall is 5.6 inches and the circumference is 79.5 inches, so the tire turns 797 times per mile.
What tire sizes are equivalent to 205/70R14?
Within 3 percent of the same diameter on the same 14-inch wheel: 195/70R14 (-2.2%), 215/70R14 (+2.2%); on a 15-inch wheel: 215/60R15 (-0.6%), 205/65R15 (+0.8%). The percentage is the diameter change, which is also your speedometer error.
Can I use 215/70R14 instead of 205/70R14?
Dimensionally yes: 215/70R14 is 2.2% taller (+14 mm) and 10 mm wider, and at a true 60 mph the speedometer would read 58.7 mph. The extra width needs about 0.20 in of clearance on each side of the tire and a rim width that suits 215 mm.