305/70R15 in inches

How tall is a 305 70R15 tire?

When converted to inches, the equivalent of a 305/70R15 tire size is 31.8x12R15. It means that:

  • height overall (or diameter) is 31.8 inches
  • tread width is 12 inches
  • wheel diameter is 15 inches

Learn more

305/70R15 tire size in inches
305/70R15 tire size chart

305/70R15 tire size in inches

305/70R15 Height / overall diameter: 31.8 inches
Height / overall diameter
31.8 inches
305/70R15 Tread width: 12 inches
Tread width
12 inches
305/70R15 Sidewall: 8.4 inches
8.4 inches
305/70R15 Wheel diameter: 15 inches
Wheel diameter
15 inches
305/70R15 Circumference: 99.9 inches
99.9 inches
305/70R15 Revolutions: 634 per mile
634 per mile

305/70R15 — 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
  • 15 is a wheel diameter (or rim) in inches

305/70R15 tire code
305/70R15 tire code

How to convert 305 70R15 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 15″ rim diameter with two of the sidewall heights. It will result in a 31.8″ total tire diameter (or height).

For your convenience, below is a table for 305/70R15 conversion to inches:

Inches Metric
Overall diameter (height) 31.8″ 808 mm
Tread width 12″ 305 mm
Wheel diameter 15″ 808 mm
Sidewall height 8.4″ 214 mm
Circumference 99.9″ 2537 mm
Revolutions 634 / ml 394 / km

Alternatives to a 305/70R15 tire

If you're looking to upsize your 305 70R15 tires, try to stay within 3% deviation of an overall diameter for safety reasons.

Tire Tire diameter Width Wheel Size
315/70R15 32.4″ 0.46% 12.4″ 15″
LT315/70R15 32.4″ 0.46% 12.4″ 15″
P305/70R15 31.8″ 0% 12″ 15″