245/70 R17 vs 31x10.50 R15

245/70 R17 vs 31x10.50 R15

31x10.50 R15 stays within the configured tolerance for 245/70 R17: +1.6% diameter and +1.6% speedometer effect.

Fitment verdict

31x10.50 R15 stays within the configured tolerance for 245/70 R17: +1.6% diameter and +1.6% speedometer effect.

Metric This size: 245/70 R17 Alternative: 31x10.50 R15 Difference Verdict
Overall diameter 30.50 in 31.00 in +1.6% Within tolerance
Section width 9.65 in 10.50 in +0.85 in Computed difference
Sidewall height 6.75 in 8.00 in +1.25 in Computed difference
Circumference 95.83 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% (+0.50 in) · US (~3%)
  • Within tolerance · Diameter +1.6%.
  • Speedo @ 60: 60 mph61.0 mph.
  • Sidewall +1.25 in · Width +0.85 in.
Diameter+1.6%+0.50 in
Speedo @ 60+1.6%60 mph61.0 mph
Sidewall+1.25 inWidth +0.85 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
30.50 in 31.00 in+0.50 in
Sidewall
6.75 in 8.00 in+1.25 in
Width
9.65 in 10.50 in+0.85 in
Circumference
95.83 in 97.39 in+1.6%
Revs / mile
661 651
Speedo @ 60
60 mph 61.0 mph+1.6%
Δ⌀ +12.6 mm
  • Current245/70 R17
  • New31x10.50 R15
  • Grounded to the road: the axle rises +0.25 in.

Result report

245/70 R17 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″ 335/55R16+0.0%+0.0%
OE 245/70R17+0.0%+0.0%
+1″ 265/60R18+0.1%+0.1%
+2″ 195/75R19+0.0%+0.0%

245/70 R17 · 31x10.50 R15 · Methodology

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