275/65 R18
What size is 275/65 R18?
275/65 R18 has an overall diameter of about 32.07 in, a section width of 10.83 in and a sidewall height of 7.04 in. It turns roughly 629 times per mile. Below are the exact figures plus in-tolerance plus/minus sizes you can switch to safely.
- Overall diameter: 32.07 in.
- Section width: 10.83 in.
- Sidewall height: 7.04 in.
- Revolutions: 391 /km · 629 /mi.
- In-tolerance sizes: 285/45 R22 (+0.1%).
Fitment verdict
285/45 R22 stays within the configured tolerance for 275/65 R18: +0.1% diameter and +0.1% speedometer effect.
| Metric | This size: 275/65 R18 | Alternative: 285/45 R22 | Difference | Verdict |
|---|---|---|---|---|
| Overall diameter | 32.07 in | 32.10 in | +0.1% | Within tolerance |
| Section width | 10.83 in | 11.22 in | +0.39 in | Computed difference |
| Sidewall height | 7.04 in | 5.05 in | -1.99 in | Computed difference |
| Circumference | 100.77 in | 100.84 in | +0.1% | Within tolerance |
| Speedo | 0.0% | +0.1% | +0.1% | Within tolerance |
Seasonal check
Planning a long summer drive?
Use the budget and running-cost tools before a trip, especially if the current tyres are worn or the replacement size changes diameter.
Specification
| Overall diameter | 32.07 in |
|---|---|
| Section width | 10.83 in |
| Sidewall height | 7.04 in |
| Circumference | 100.77 in |
| Revolutions | 391 /km · 629 /mi |
In-tolerance sizes
Alternative sizes that stay within the safe diameter tolerance:
| Size | Diameter | Speedo | Verdict |
|---|---|---|---|
| 285/45 R22 | +0.1% | +0.1% | ✓ OK |
| 275/55 R20 | -0.5% | -0.5% | ✓ OK |
| 275/45 R22 | -1.0% | -1.0% | ✓ OK |
| 265/70 R17 | -1.5% | -1.5% | ✓ OK |
| 305/40 R22 | -1.5% | -1.5% | ✓ OK |
| 265/65 R18 | -1.6% | -1.6% | ✓ OK |
| 285/65 R18 | +1.6% | +1.6% | ✓ OK |
| 285/60 R18 | -1.9% | -1.9% | ✓ OK |
| 305/45 R22 | +2.3% | +2.3% | ✓ OK |
| 285/50 R20 | -2.7% | -2.7% | ✓ OK |
| 33x12.50 R15 | +2.9% | +2.9% | ✓ OK |
| 33x12.50 R16 | +2.9% | +2.9% | ✓ OK |
Compare sizes
- Within tolerance · Diameter +0.1%.
- Speedo @ 60: 60 mph → 60.0 mph.
- Sidewall -1.99 in · Width +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
- 32.07 in 32.10 in+0.02 in
- Sidewall
- 7.04 in 5.05 in-1.99 in
- Width
- 10.83 in 11.22 in+0.39 in
- Circumference
- 100.77 in 100.84 in+0.1%
- Revs / mile
- 629 628
- Speedo @ 60
- 60 mph 60.0 mph+0.1%
- Current —
275/65 R18 - New —
285/45 R22 - Grounded to the road: the axle rises +0.01 in.
Result report
275/65 R18 285/45 R22 · Within tolerance
Use this size when shopping: 285/45 R22
Geometric estimate. Always verify physical clearance (arches, suspension, brakes) before fitting.
Safe alternative sizes
| Size | Diameter | Speedo @ 100 | Use this |
|---|---|---|---|
−1″ 255/75R17 | -0.0% | -0.0% | |
OE 275/65R18 | +0.0% | +0.0% | |
+1″ 255/65R19 | -0.1% | -0.1% | |
+2″ 255/60R20 | -0.1% | -0.1% |
More tools
- How to read a tire size
- Plus sizing guide
- Speedometer error guide
- 275mm Section width guide
- /65 Aspect ratio guide
- Rim diameter 18"
- Load index chart
- Speed rating chart
- Rim width and tyre fitment guide
- Wheel offset guide
- Wheel spacers guide
- Tyre pressure for heavy loads and towing
What changed
- Reviewed deterministic geometry, load/speed references, sitemap inclusion and localized page shell.