Tire Size Calculator
Calculate tire sizes in inches or millimeters and find alternative sizes.
Inches
Millimeters
Results for 285/30R18 Tires
Diameter
24.7"
Width
11.2"
Sidewall
3.4"
Circumference
77.7"
Revs per mile
816
Alternate Tire Sizes
18"
13"
14"
15"
16"
17"
19"
20"
Tire Size
Diameter
Width
Sidewall
Circumference
Revs per mile