Best 325/30 R18 tires
We don't have rated tires listed in this size yet — the conversion, rim fitment and comparisons below still apply.
25.7″
overall diameter
12.8″
section width
18″
rim diameter
785.4
revs per mile
Conversion
325/30 R18 in inches
| Overall diameter | 25.7″ |
| Section width | 12.8″ |
| Rim diameter | 18″ |
| Sidewall height | 98 mm |
| Circumference | 80.7″ |
| Revolutions per mile | 785.4 |
The closest flotation size is 28x12.00R18 — 9% taller and 6.2% narrower. Compare them in the calculator.
Wheels
What rims fit 325/30 R18 tires?
A tire fits a range of rim widths. Too narrow or too wide and the sidewall changes shape.
Minimum
9″
Ideal
10″
Maximum
11.5″
Rim diameter is fixed at 18″ — only the width varies. Estimated from the 12.8″ section width (70–90% rule).
Fitted from the factory on rims: 18x12.
Sidewall
325/30 R18 — what does it mean?
| Parameter | Meaning |
|---|---|
| 325 | The first number is the section width — 325 mm, or about 12.8 inches across the widest part of the tire. |
| 30 | The second number is the aspect ratio: sidewall height as a percentage of width. At 30%, the sidewall is about 98 mm tall. |
| R18 | R means radial construction, which nearly all modern tires use. The number is the rim diameter in inches — this tire fits a 18-inch wheel. |