245/65 R18
What size is 245/65 R18?
245/65 R18 has an overall diameter of about 30.54 in, a section width of 9.65 in and a sidewall height of 6.27 in. It turns roughly 660 times per mile. Below are the exact figures plus in-tolerance plus/minus sizes you can switch to safely.
- Overall diameter: 30.54 in.
- Section width: 9.65 in.
- Sidewall height: 6.27 in.
- Revolutions: 410 /km · 660 /mi.
- In-tolerance sizes: 265/60 R18 (-0.1%).
Fitment verdict
265/60 R18 stays within the configured tolerance for 245/65 R18: -0.1% diameter and -0.1% speedometer effect.
| Metric | This size: 245/65 R18 | Alternative: 265/60 R18 | Difference | Verdict |
|---|---|---|---|---|
| Overall diameter | 30.54 in | 30.52 in | -0.1% | Within tolerance |
| Section width | 9.65 in | 10.43 in | +0.79 in | Computed difference |
| Sidewall height | 6.27 in | 6.26 in | -0.01 in | Computed difference |
| Circumference | 95.94 in | 95.88 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 | 30.54 in |
|---|---|
| Section width | 9.65 in |
| Sidewall height | 6.27 in |
| Circumference | 95.94 in |
| Revolutions | 410 /km · 660 /mi |
In-tolerance sizes
Alternative sizes that stay within the safe diameter tolerance:
| Size | Diameter | Speedo | Verdict |
|---|---|---|---|
| 265/60 R18 | -0.1% | -0.1% | ✓ OK |
| 265/65 R17 | +0.1% | +0.1% | ✓ OK |
| 245/70 R17 | -0.1% | -0.1% | ✓ OK |
| 265/70 R16 | +0.2% | +0.2% | ✓ OK |
| 265/50 R20 | -0.3% | -0.3% | ✓ OK |
| 265/45 R21 | -0.5% | -0.5% | ✓ OK |
| 265/40 R22 | -0.6% | -0.6% | ✓ OK |
| 275/45 R21 | +0.7% | +0.7% | ✓ OK |
| 275/55 R19 | +1.2% | +1.2% | ✓ OK |
| 285/40 R22 | +1.4% | +1.4% | ✓ OK |
| 31x10.50 R15 | +1.5% | +1.5% | ✓ OK |
| 31x10.50 R16 | +1.5% | +1.5% | ✓ OK |
Compare sizes
- Within tolerance · Diameter -0.1%.
- Speedo @ 60: 60 mph → 60.0 mph.
- Sidewall -0.01 in · Width +0.79 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
- 30.54 in 30.52 in-0.02 in
- Sidewall
- 6.27 in 6.26 in-0.01 in
- Width
- 9.65 in 10.43 in+0.79 in
- Circumference
- 95.94 in 95.88 in-0.1%
- Revs / mile
- 660 661
- Speedo @ 60
- 60 mph 60.0 mph-0.1%
- Current —
245/65 R18 - New —
265/60 R18 - Grounded to the road: the axle rises -0.01 in.
Result report
245/65 R18 265/60 R18 · Within tolerance
Use this size when shopping: 265/60 R18
Geometric estimate. Always verify physical clearance (arches, suspension, brakes) before fitting.
Safe alternative sizes
| Size | Diameter | Speedo @ 100 | Use this |
|---|---|---|---|
−1″ 215/80R17 | +0.0% | +0.0% | |
OE 245/65R18 | +0.0% | +0.0% | |
+1″ 195/75R19 | -0.1% | -0.1% | |
+2″ 335/40R20 | +0.0% | +0.0% |
More tools
- How to read a tire size
- Plus sizing guide
- Speedometer error guide
- 245mm 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.