182Best 305/35 R21 tires
5 rated tires available in this size, scored on dry, wet, snow, comfort and wear. Top overall right now is the Michelin Pilot Alpin 5 SUV at 82/100.
29.4″
overall diameter
12″
section width
21″
rim diameter
685.9
revs per mile
Best 305/35 R21 winter tires
3182
281
380Best 305/35 R21 summer tires
1
174More top-rated 305/35 R21 tires
1
174Conversion
305/35 R21 in inches
| Overall diameter | 29.4″ |
| Section width | 12″ |
| Rim diameter | 21″ |
| Sidewall height | 107 mm |
| Circumference | 92.4″ |
| Revolutions per mile | 685.9 |
Wheels
What rims fit 305/35 R21 tires?
A tire fits a range of rim widths. Too narrow or too wide and the sidewall changes shape.
Minimum
8.5″
Ideal
9.5″
Maximum
11″
Rim diameter is fixed at 21″ — only the width varies. Estimated from the 12″ section width (70–90% rule).
Fitted from the factory on rims: 21x10.5, 21x11.
Popular comparisons
Sizes often compared with 305/35 R21
Close alternatives — each opens in the tire size calculator.
Sidewall
305/35 R21 — what does it mean?
| Parameter | Meaning |
|---|---|
| 305 | The first number is the section width — 305 mm, or about 12 inches across the widest part of the tire. |
| 35 | The second number is the aspect ratio: sidewall height as a percentage of width. At 35%, the sidewall is about 107 mm tall. |
| R21 | R means radial construction, which nearly all modern tires use. The number is the rim diameter in inches — this tire fits a 21-inch wheel. |