183Best 255/50 R21 tires
8 rated tires available in this size, scored on dry, wet, snow, comfort and wear. Top overall right now is the Nokian Hakkapeliitta R5 EV at 93/100.
31″
overall diameter
10″
section width
21″
rim diameter
649.8
revs per mile
Best 255/50 R21 summer tires
4183
370
469Best 255/50 R21 all-season tires
2
178
265More top-rated 255/50 R21 tires
1
193Best 255/50 R21 winter tires
1
175Conversion
255/50 R21 in inches
| Overall diameter | 31″ |
| Section width | 10″ |
| Rim diameter | 21″ |
| Sidewall height | 128 mm |
| Circumference | 97.5″ |
| Revolutions per mile | 649.8 |
Wheels
What rims fit 255/50 R21 tires?
A tire fits a range of rim widths. Too narrow or too wide and the sidewall changes shape.
Minimum
7″
Ideal
8″
Maximum
9″
Rim diameter is fixed at 21″ — only the width varies. Estimated from the 10″ section width (70–90% rule).
Fitted from the factory on rims: 21x8, 21x8.5, 21x9.
Popular comparisons
Sizes often compared with 255/50 R21
Close alternatives — each opens in the tire size calculator.
Sidewall
255/50 R21 — what does it mean?
| Parameter | Meaning |
|---|---|
| 255 | The first number is the section width — 255 mm, or about 10 inches across the widest part of the tire. |
| 50 | The second number is the aspect ratio: sidewall height as a percentage of width. At 50%, the sidewall is about 128 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. |