285/60 R18

What size is 285/60 R18?

285/60 R18 has an overall diameter of about 31.46 in, a section width of 11.22 in and a sidewall height of 6.73 in. It turns roughly 641 times per mile. Below are the exact figures plus in-tolerance plus/minus sizes you can switch to safely.

Fitment verdict

265/65 R18 stays within the configured tolerance for 285/60 R18: +0.3% diameter and +0.3% speedometer effect.

Metric This size: 285/60 R18 Alternative: 265/65 R18 Difference Verdict
Overall diameter 31.46 in 31.56 in +0.3% Within tolerance
Section width 11.22 in 10.43 in -0.79 in Computed difference
Sidewall height 6.73 in 6.78 in +0.05 in Computed difference
Circumference 98.85 in 99.16 in +0.3% Within tolerance
Speedo 0.0% +0.3% +0.3% 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.

Estimate tyre budget

Specification

Overall diameter31.46 in
Section width11.22 in
Sidewall height6.73 in
Circumference98.85 in
Revolutions 398 /km · 641 /mi

In-tolerance sizes

Alternative sizes that stay within the safe diameter tolerance:

Size Diameter Speedo Verdict
265/65 R18 +0.3% +0.3% ✓ OK
265/70 R17 +0.5% +0.5% ✓ OK
305/40 R22 +0.5% +0.5% ✓ OK
285/50 R20 -0.8% -0.8% ✓ OK
275/45 R22 +0.9% +0.9% ✓ OK
275/55 R20 +1.4% +1.4% ✓ OK
31x10.50 R15 -1.5% -1.5% ✓ OK
31x10.50 R16 -1.5% -1.5% ✓ OK
285/40 R22 -1.6% -1.6% ✓ OK
275/55 R19 -1.8% -1.8% ✓ OK
275/65 R18 +1.9% +1.9% ✓ OK
285/45 R22 +2.0% +2.0% ✓ OK

Compare sizes

Looks valid
Looks valid
Units
✓ Within toleranceDiameter +0.3% (+0.10 in) · US (~3%)
  • Within tolerance · Diameter +0.3%.
  • Speedo @ 60: 60 mph60.2 mph.
  • Sidewall +0.05 in · Width -0.79 in.
Diameter+0.3%+0.10 in
Speedo @ 60+0.3%60 mph60.2 mph
Sidewall+0.05 inWidth -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
31.46 in 31.56 in+0.10 in
Sidewall
6.73 in 6.78 in+0.05 in
Width
11.22 in 10.43 in-0.79 in
Circumference
98.85 in 99.16 in+0.3%
Revs / mile
641 639
Speedo @ 60
60 mph 60.2 mph+0.3%
Δ⌀ +2.5 mm
  • Current285/60 R18
  • New265/65 R18
  • Grounded to the road: the axle rises +0.05 in.

Result report

285/60 R18 265/65 R18 · Within tolerance

Use this size when shopping: 265/65 R18

Use this size when shopping

Geometric estimate. Always verify physical clearance (arches, suspension, brakes) before fitting.

Safe alternative sizes

SizeDiameterSpeedo @ 100Use this
−1″ 245/75R17+0.0%+0.0%
OE 285/60R18+0.0%+0.0%
+1″ 265/60R19+0.2%+0.2%
+2″ 265/55R20+0.0%+0.0%

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Last reviewed: 2026-06-28

Last reviewed: 2026-06-28
What changed
  • Reviewed deterministic geometry, load/speed references, sitemap inclusion and localized page shell.