265/60 R18 vs 31x10.50 R15

265/60 R18 vs 31x10.50 R15

31x10.50 R15 stays within the configured tolerance for 265/60 R18: +1.6% diameter and +1.6% speedometer effect.

Fitment verdict

31x10.50 R15 stays within the configured tolerance for 265/60 R18: +1.6% diameter and +1.6% speedometer effect.

Metric This size: 265/60 R18 Alternative: 31x10.50 R15 Difference Verdict
Overall diameter 30.52 in 31.00 in +1.6% Within tolerance
Section width 10.43 in 10.50 in +0.07 in Computed difference
Sidewall height 6.26 in 8.00 in +1.74 in Computed difference
Circumference 95.88 in 97.39 in +1.6% Within tolerance
Speedo 0.0% +1.6% +1.6% Within tolerance

Compare sizes

Looks valid
Looks valid
Units
✓ Within toleranceDiameter +1.6% (+0.48 in) · US (~3%)
  • Within tolerance · Diameter +1.6%.
  • Speedo @ 60: 60 mph60.9 mph.
  • Sidewall +1.74 in · Width +0.07 in.
Diameter+1.6%+0.48 in
Speedo @ 60+1.6%60 mph60.9 mph
Sidewall+1.74 inWidth +0.07 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
30.52 in 31.00 in+0.48 in
Sidewall
6.26 in 8.00 in+1.74 in
Width
10.43 in 10.50 in+0.07 in
Circumference
95.88 in 97.39 in+1.6%
Revs / mile
661 651
Speedo @ 60
60 mph 60.9 mph+1.6%
Δ⌀ +12.2 mm
  • Current265/60 R18
  • New31x10.50 R15
  • Grounded to the road: the axle rises +0.24 in.

Result report

265/60 R18 31x10.50 R15 · Within tolerance

Use this size when shopping: 31x10.50 R15

Use this size when shopping

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

Safe alternative sizes

SizeDiameterSpeedo @ 100Use this
−1″ 245/70R17-0.1%-0.1%
OE 265/60R18+0.0%+0.0%
+1″ 195/75R19-0.0%-0.0%
+2″ 205/65R20-0.1%-0.1%

265/60 R18 · 31x10.50 R15 · Methodology

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