215/70 R15 vs 255/40 R19

255/40 R19 stays within the configured tolerance for 215/70 R15: +0.7% diameter and +0.7% speedometer effect.

Geometric comparison

255/40 R19 stays within the configured tolerance for 215/70 R15: +0.7% diameter and +0.7% speedometer effect.

Geometric comparison
Metric	This size: 215/70 R15	Alternative: 255/40 R19	Difference	Verdict
Overall diameter	26.85 in	27.03 in	+0.7%	Within tolerance
Section width	8.46 in	10.04 in	+1.57 in	Computed difference
Sidewall height	5.93 in	4.02 in	-1.91 in	Computed difference
Circumference	84.35 in	84.92 in	+0.7%	Within tolerance
Speedo	0.0%	+0.7%	+0.7%	Within tolerance

Compare sizes

Current tireLooks valid

New tireLooks valid

Market

Units

Not recommendedWithin tolerance · Diameter +0.7% (+0.18 in) · US (~3%)

Not recommended · This rating covers tire geometry only, not vehicle compatibility.
Diameter +0.7% · Ride-height change +0.09 in.
Speedometer reads low · 60 mph → 60.4 mph.
Sidewall -1.91 in · Width +1.57 in.

Diameter+0.7%+0.18 in

Speedo @ 60+0.7%60 mph → 60.4 mph

Sidewall-1.91 inWidth +1.57 in

Ride-height change+0.09 inDiameter ÷ 2

How this result is calculated

Computed from nominal tire-size geometry: diameter, circumference and speedometer error. It does not check vehicle placard approval, load/speed rating, rim-width range, wheel-arch, suspension or brake clearance.

Methodology

Before fitting

Check the vehicle placard and owner’s manual first.
Match or exceed the required load index and speed rating.
Confirm rim-width range, bolt pattern, hub bore, offset and fasteners.
Inspect wheel-arch, suspension and brake clearance under real vehicle load.
Check TPMS, cold pressure and local roadworthiness rules.

Diameter: 26.85 in 27.03 in+0.18 in
Sidewall: 5.93 in 4.02 in-1.91 in
Width: 8.46 in 10.04 in+1.57 in
Circumference: 84.35 in 84.92 in+0.7%
Revs / mile: 751 746
Speedo @ 60: 60 mph 60.4 mph+0.7%
Ride-height change: 0.00 in +0.09 in
True distance per 100 indicated: 100 mi 100.7 mi+0.7%

Current — 215/70 R15
New — 255/40 R19
Grounded to the road: the axle rises +0.09 in.

Result report

215/70 R15 255/40 R19 · Not recommended · Within tolerance

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Markdown link

[215/70 R15 vs 255/40 R19 Tire size comparison](https://tirefitlab.com/tire-size-calculator/?from=215%2F70+R15&to=255%2F40+R19&market=us)

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

In-tolerance alternative sizes

In-tolerance alternative sizes
Size	Diameter	Speedo @ 100	Use this
OE `215/70R15`	+0.0%	+0.0%

215/70 R15 · 255/40 R19 · Methodology

Technical check: 2026-06-28

What changed

Checked generated routes, metadata, sitemap inclusion and localized page rendering.

Methodology