31x10.50 R15 vs 285/60 R18
31x10.50 R15 vs 285/60 R18
285/60 R18 stays within the configured tolerance for 31x10.50 R15: +1.5% diameter and +1.5% speedometer effect.
Fitment verdict
285/60 R18 stays within the configured tolerance for 31x10.50 R15: +1.5% diameter and +1.5% speedometer effect.
| Metric | This size: 31x10.50 R15 | Alternative: 285/60 R18 | Difference | Verdict |
|---|---|---|---|---|
| Overall diameter | 31.00 in | 31.46 in | +1.5% | Within tolerance |
| Section width | 10.50 in | 11.22 in | +0.72 in | Computed difference |
| Sidewall height | 8.00 in | 6.73 in | -1.27 in | Computed difference |
| Circumference | 97.39 in | 98.85 in | +1.5% | Within tolerance |
| Speedo | 0.0% | +1.5% | +1.5% | Within tolerance |
Compare sizes
Looks valid
Looks valid
Units
✓ Within toleranceDiameter +1.5% (+0.46 in) · US (~3%)
- Within tolerance · Diameter +1.5%.
- Speedo @ 60: 60 mph → 60.9 mph.
- Sidewall -1.27 in · Width +0.72 in.
Diameter+1.5%+0.46 in
Speedo @ 60+1.5%60 mph → 60.9 mph
Sidewall-1.27 inWidth +0.72 in
How this result is calculated
Computed from nominal tire-size geometry: diameter, circumference and speedometer error. It does not check wheel-arch, suspension or brake clearance.
Methodology- Diameter
- 31.00 in 31.46 in+0.46 in
- Sidewall
- 8.00 in 6.73 in-1.27 in
- Width
- 10.50 in 11.22 in+0.72 in
- Circumference
- 97.39 in 98.85 in+1.5%
- Revs / mile
- 651 641
- Speedo @ 60
- 60 mph 60.9 mph+1.5%
- Current —
31x10.50 R15 - New —
285/60 R18 - Grounded to the road: the axle rises +0.23 in.
Result report
31x10.50 R15 285/60 R18 · Within tolerance
Use this size when shopping: 285/60 R18
Geometric estimate. Always verify physical clearance (arches, suspension, brakes) before fitting.
Safe alternative sizes
| Size | Diameter | Speedo @ 100 | Use this |
|---|---|---|---|
−1″ 335/65R14 | +0.5% | +0.5% | |
OE 255/80R15 | +0.2% | +0.2% | |
+1″ 345/55R16 | -0.2% | -0.2% | |
+2″ 355/50R17 | -0.1% | -0.1% |
31x10.50 R15 · 285/60 R18 · Methodology
What changed
- Reviewed deterministic geometry, load/speed references, sitemap inclusion and localized page shell.