305/70R18 in inches

How tall is a 305 70R18 tire?

When converted to inches, the equivalent of a 305/70R18 tire size is 34.8x12R18. It means that:

  • height overall (or diameter) is 34.8 inches
  • tread width is 12 inches
  • wheel diameter is 18 inches

Learn more

305/70R18 tire size in inches
305/70R18 tire size chart

305/70R18 tire size in inches

305/70R18 Height / overall diameter: 34.8 inches
Height / overall diameter
34.8 inches
305/70R18 Tread width: 12 inches
Tread width
12 inches
305/70R18 Sidewall: 8.4 inches
Sidewall
8.4 inches
305/70R18 Wheel diameter: 18 inches
Wheel diameter
18 inches
305/70R18 Circumference: 109.3 inches
Circumference
109.3 inches
305/70R18 Revolutions: 579 per mile
Revolutions
579 per mile

305/70R18 — what does it mean?

  • 305 stands for tread width in millimeters
  • 70 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

305/70R18 tire code
305/70R18 tire code

How to convert 305 70R18 to inches?

First of all, we need to divide 305 mm (width) by 25.4 (mm to inch conversion), which will give us a width of 12″. Then, 70% of the 12″ will result in 8.4″ 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 34.8″ total tire diameter (or height).

For your convenience, below is a table for 305/70R18 conversion to inches:

Inches Metric
Overall diameter (height) 34.8″ 884 mm
Tread width 12″ 305 mm
Wheel diameter 18″ 884 mm
Sidewall height 8.4″ 214 mm
Circumference 109.3″ 2776 mm
Revolutions 579 / ml 360 / km

Alternatives to a 305/70R18 tire

If you're looking to upsize your 305 70R18 tires, try to stay within 3% deviation of an overall diameter for safety reasons.

Tire Tire diameter Width Wheel Size
325/65R18 34.6″ -0.14% 12.8″ 18″
LT325/65R18 34.6″ -0.14% 12.8″ 18″
285/75R18 34.8″ 0% 11.2″ 18″
295/70R18 34.2″ -0.43% 11.6″ 18″
LT295/70R18 34.2″ -0.43% 11.6″ 18″
315/70R18 35.4″ 0.42% 12.4″ 18″
275/80R18 35.4″ 0.42% 10.8″ 18″
345/60R18 34.2″ -0.43% 13.6″ 18″
375/60R18 35.8″ 0.7% 14.8″ 18″
LT275/80R18 35.4″ 0.42% 10.8″ 18″