235/45 R18 vs 245/45 R18
235/45 R18 vs 245/45 R18
245/45 R18 stays within the configured tolerance for 235/45 R18: +1.3% diameter and +1.3% speedometer effect.
Fitment verdict
245/45 R18 stays within the configured tolerance for 235/45 R18: +1.3% diameter and +1.3% speedometer effect.
| Metric | This size: 235/45 R18 | Alternative: 245/45 R18 | Difference | Verdict |
|---|---|---|---|---|
| Overall diameter | 26.33 in | 26.68 in | +1.3% | Within tolerance |
| Section width | 9.25 in | 9.65 in | +0.39 in | Computed difference |
| Sidewall height | 4.16 in | 4.34 in | +0.18 in | Computed difference |
| Circumference | 82.71 in | 83.82 in | +1.3% | Within tolerance |
| Speedo | 0.0% | +1.3% | +1.3% | Within tolerance |
Compare sizes
Looks valid
Looks valid
Units
✓ Within toleranceDiameter +1.3% (+0.35 in) · US (~3%)
- Within tolerance · Diameter +1.3%.
- Speedo @ 60: 60 mph → 60.8 mph.
- Sidewall +0.18 in · Width +0.39 in.
Diameter+1.3%+0.35 in
Speedo @ 60+1.3%60 mph → 60.8 mph
Sidewall+0.18 inWidth +0.39 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
- 26.33 in 26.68 in+0.35 in
- Sidewall
- 4.16 in 4.34 in+0.18 in
- Width
- 9.25 in 9.65 in+0.39 in
- Circumference
- 82.71 in 83.82 in+1.3%
- Revs / mile
- 766 756
- Speedo @ 60
- 60 mph 60.8 mph+1.3%
- Current —
235/45 R18 - New —
245/45 R18 - Grounded to the road: the axle rises +0.18 in.
Result report
235/45 R18 245/45 R18 · Within tolerance
Use this size when shopping: 245/45 R18
Geometric estimate. Always verify physical clearance (arches, suspension, brakes) before fitting.
Safe alternative sizes
| Size | Diameter | Speedo @ 100 | Use this |
|---|---|---|---|
−1″ 215/55R17 | -0.1% | -0.1% | |
OE 235/45R18 | +0.0% | +0.0% | |
+1″ 155/60R19 | -0.0% | -0.0% | |
+2″ 145/55R20 | -0.2% | -0.2% |
235/45 R18 · 245/45 R18 · Methodology
What changed
- Reviewed deterministic geometry, load/speed references, sitemap inclusion and localized page shell.