275/40 R20 vs 245/45 R20
275/40 R20 vs 245/45 R20
245/45 R20 stays within the configured tolerance for 275/40 R20: +0.1% diameter and +0.1% speedometer effect.
Fitment verdict
245/45 R20 stays within the configured tolerance for 275/40 R20: +0.1% diameter and +0.1% speedometer effect.
| Metric | This size: 275/40 R20 | Alternative: 245/45 R20 | Difference | Verdict |
|---|---|---|---|---|
| Overall diameter | 28.66 in | 28.68 in | +0.1% | Within tolerance |
| Section width | 10.83 in | 9.65 in | -1.18 in | Computed difference |
| Sidewall height | 4.33 in | 4.34 in | +0.01 in | Computed difference |
| Circumference | 90.04 in | 90.10 in | +0.1% | Within tolerance |
| Speedo | 0.0% | +0.1% | +0.1% | Within tolerance |
Compare sizes
Looks valid
Looks valid
Units
✓ Within toleranceDiameter +0.1% (+0.02 in) · US (~3%)
- Within tolerance · Diameter +0.1%.
- Speedo @ 60: 60 mph → 60.0 mph.
- Sidewall +0.01 in · Width -1.18 in.
Diameter+0.1%+0.02 in
Speedo @ 60+0.1%60 mph → 60.0 mph
Sidewall+0.01 inWidth -1.18 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
- 28.66 in 28.68 in+0.02 in
- Sidewall
- 4.33 in 4.34 in+0.01 in
- Width
- 10.83 in 9.65 in-1.18 in
- Circumference
- 90.04 in 90.10 in+0.1%
- Revs / mile
- 704 703
- Speedo @ 60
- 60 mph 60.0 mph+0.1%
- Current —
275/40 R20 - New —
245/45 R20 - Grounded to the road: the axle rises +0.01 in.
Result report
275/40 R20 245/45 R20 · Within tolerance
Use this size when shopping: 245/45 R20
Geometric estimate. Always verify physical clearance (arches, suspension, brakes) before fitting.
Safe alternative sizes
| Size | Diameter | Speedo @ 100 | Use this |
|---|---|---|---|
−1″ 175/70R19 | -0.1% | -0.1% | |
OE 275/40R20 | +0.0% | +0.0% | |
+1″ 195/50R21 | +0.1% | +0.1% | |
+2″ 155/55R22 | +0.2% | +0.2% |
275/40 R20 · 245/45 R20 · Methodology
What changed
- Reviewed deterministic geometry, load/speed references, sitemap inclusion and localized page shell.