P215/55R18 in inches

How tall is a P215 55R18 tire?

When converted to inches, the equivalent of a P215/55R18 tire size is 27.2x8.5R18. It means that:

  • height overall (or diameter) is 27.2 inches
  • tread width is 8.5 inches
  • wheel diameter is 18 inches

Learn more

P215/55R18 tire size in inches
P215/55R18 tire size chart

P215/55R18 tire size in inches

P215/55R18 Height / overall diameter: 27.2 inches
Height / overall diameter
27.2 inches
P215/55R18 Tread width: 8.5 inches
Tread width
8.5 inches
P215/55R18 Sidewall: 4.6 inches
Sidewall
4.6 inches
P215/55R18 Wheel diameter: 18 inches
Wheel diameter
18 inches
P215/55R18 Circumference: 85.4 inches
Circumference
85.4 inches
P215/55R18 Revolutions: 742 per mile
Revolutions
742 per mile

P215/55R18 — what does it mean?

  • P means "passenger car"
  • 215 stands for tread width in millimeters
  • 55 is an aspect ration between the tread width and the sidewall in percents
  • R means that the tire has a radial construction
  • 18 is a wheel diameter (or rim) in inches

P215/55R18 tire code
P215/55R18 tire code

How to convert P215 55R18 to inches?

First of all, we need to divide 215 mm (width) by 25.4 (mm to inch conversion), which will give us a width of 8.5″. Then, 55% of the 8.5″ will result in 4.6″ sidewall.

To get the total height or tire diameter, we need to sum the 18″ rim diameter with two of the sidewall heights. It will result in a 27.2″ total tire diameter (or height).

For your convenience, below is a table for P215/55R18 conversion to inches:

Inches Metric
Overall diameter (height) 27.2″ 691 mm
Tread width 8.5″ 215 mm
Wheel diameter 18″ 691 mm
Sidewall height 4.6″ 118 mm
Circumference 85.4″ 2170 mm
Revolutions 742 / ml 461 / km

Alternatives to a P215/55R18 tire

If you're looking to upsize your P215 55R18 tires, try to stay within 3% deviation of an overall diameter for safety reasons.

Tire Tire diameter Width Wheel Size
245/45R18 26.6″ -0.55% 9.6″ 18″
275/40R18 26.6″ -0.55% 10.8″ 18″
135/80R18 26.6″ -0.55% 5.3″ 18″
145/80R18 27.2″ 0% 5.7″ 18″
145/85R18 27.6″ 0.36% 5.7″ 18″
155/70R18 26.6″ -0.55% 6.1″ 18″
155/80R18 27.8″ 0.54% 6.1″ 18″
165/70R18 27.2″ 0% 6.5″ 18″
T165/70R18 27.2″ 0% 6.5″ 18″
205/60R18 27.6″ 0.36% 8.1″ 18″