225/55 R17 vs 255/40 R19

225/55 R17 vs 255/40 R19

255/40 R19 stays within the configured tolerance for 225/55 R17: +1.1% diameter and +1.1% speedometer effect.

Fitment verdict

255/40 R19 stays within the configured tolerance for 225/55 R17: +1.1% diameter and +1.1% speedometer effect.

Metric This size: 225/55 R17 Alternative: 255/40 R19 Difference Verdict
Overall diameter 26.74 in 27.03 in +1.1% Within tolerance
Section width 8.86 in 10.04 in +1.18 in Computed difference
Sidewall height 4.87 in 4.02 in -0.86 in Computed difference
Circumference 84.02 in 84.92 in +1.1% Within tolerance
Speedo 0.0% +1.1% +1.1% Within tolerance

Compare sizes

Looks valid
Looks valid
Units
✓ Within toleranceDiameter +1.1% (+0.29 in) · US (~3%)
  • Within tolerance · Diameter +1.1%.
  • Speedo @ 60: 60 mph60.6 mph.
  • Sidewall -0.86 in · Width +1.18 in.
Diameter+1.1%+0.29 in
Speedo @ 60+1.1%60 mph60.6 mph
Sidewall-0.86 inWidth +1.18 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
26.74 in 27.03 in+0.29 in
Sidewall
4.87 in 4.02 in-0.86 in
Width
8.86 in 10.04 in+1.18 in
Circumference
84.02 in 84.92 in+1.1%
Revs / mile
754 746
Speedo @ 60
60 mph 60.6 mph+1.1%
Δ⌀ +7.3 mm
  • Current225/55 R17
  • New255/40 R19
  • Grounded to the road: the axle rises +0.14 in.

Result report

225/55 R17 255/40 R19 · Within tolerance

Use this size when shopping: 255/40 R19

Use this size when shopping

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

Safe alternative sizes

SizeDiameterSpeedo @ 100Use this
−1″ 195/70R16+0.0%+0.0%
OE 225/55R17+0.0%+0.0%
+1″ 185/60R18-0.0%-0.0%
+2″ 245/40R19-0.1%-0.1%

225/55 R17 · 255/40 R19 · Methodology

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