GarageCalc What 215/70R16 means
215 is the section width in millimeters (8.5 in). 70 is the aspect ratio: the sidewall is 70 percent of the width, so 215 × 0.70 = 151 mm (5.9 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 × 151 = 707 mm, or 27.9 in.
A full marking adds a load index and speed rating after the size, for example 215/70R16 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 215/70R16
Going up one wheel size, the closest match is 215/65R17 at +0.6% diameter with a 140 mm sidewall instead of 151 mm. Going down one size, 235/70R15 is +0.4% with a taller 165 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 215/70R16 tire?
27.9 inches (707 mm) in overall diameter: the 16-inch wheel (406 mm) plus two 151 mm sidewalls. Real tires land within about 1 to 2 percent of that depending on brand, tread depth and pressure.
What is 215/70R16 in inches?
27.9 x 8.5 R16: 27.9 inches tall, 8.5 inches wide, on a 16-inch wheel. The sidewall is 5.9 inches and the circumference is 87.5 inches, so the tire turns 724 times per mile.
What tire sizes are equivalent to 215/70R16?
Within 3 percent of the same diameter on the same 16-inch wheel: 235/65R16 (+0.6%), 225/65R16 (-1.2%), 225/70R16 (+2.0%); on a 17-inch wheel: 215/65R17 (+0.6%), 225/60R17 (-0.8%); on a 15-inch wheel: 235/70R15 (+0.4%), 215/75R15 (-0.6%). The percentage is the diameter change, which is also your speedometer error.
Can I use 225/65R16 instead of 215/70R16?
Dimensionally yes: 225/65R16 is 1.2% 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 225 mm.