285/45R21 vs 255/45R22 tire size
255/45R22 vs 285/45R21, diameter
-0.2% shorter
- Speedometer
- 60.1 mph
- At a true 60 mph
- Diameter
- 31.04 in
- Was 31.10 in
- Revs per mile
- 650
- Was 649
- 3% guideline
- Within
Car built for 285/45R21, now on 255/45R22.
285/45R21 and 255/45R22
| Measure | 285/45R21 | 255/45R22 | Difference |
|---|---|---|---|
| Width, mm | 285 | 255 | -30 |
| Sidewall, % of width | 45 | 45 | 0 |
| Rim, in | 21 | 22 | +1 |
| Section height, in | 5.05 | 4.52 | -0.53 |
| Diameter, in | 31.10 | 31.04 | -0.06 (-0.2%) |
| Circumference, in | 97.7 | 97.5 | -0.2 |
| Revs per mile | 649 | 650 | +1 (+0.2%) |
Fitting 255/45R22 instead of 285/45R21
Within the usual 3% diameter guideline.
- Needs 22 in wheels.
- Shorter sidewall: 0.5 in less.
Cars with 285/45R21
Cars with 255/45R22
What this cannot tell you
Diameter within 3% is a common shop guideline, not a maker spec.
Load index, offset and clearance are not in this data.
- Two or more sources agree
- One source
- Model-level or estimate
- Sources differ