255/45 R19

What size is 255/45 R19?

255/45 R19 has an overall diameter of about 28.04 in, a section width of 10.04 in and a sidewall height of 4.52 in. It turns roughly 719 times per mile. Below are the exact figures plus in-tolerance plus/minus sizes you can switch to safely.

Fitment verdict

235/65 R16 stays within the configured tolerance for 255/45 R19: 0.0% diameter and 0.0% speedometer effect.

Metric This size: 255/45 R19 Alternative: 235/65 R16 Difference Verdict
Overall diameter 28.04 in 28.03 in 0.0% Within tolerance
Section width 10.04 in 9.25 in -0.79 in Computed difference
Sidewall height 4.52 in 6.01 in +1.50 in Computed difference
Circumference 88.08 in 88.05 in 0.0% Within tolerance
Speedo 0.0% 0.0% 0.0% 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 diameter28.04 in
Section width10.04 in
Sidewall height4.52 in
Circumference88.08 in
Revolutions 447 /km · 719 /mi

In-tolerance sizes

Alternative sizes that stay within the safe diameter tolerance:

Size Diameter Speedo Verdict
235/65 R16 -0.0% -0.0% ✓ OK
255/35 R21 -0.0% -0.0% ✓ OK
215/65 R17 -0.1% -0.1% ✓ OK
235/60 R17 +0.2% +0.2% ✓ OK
235/55 R18 +0.5% +0.5% ✓ OK
235/50 R19 +0.8% +0.8% ✓ OK
225/55 R18 -1.0% -1.0% ✓ OK
245/45 R19 -1.3% -1.3% ✓ OK
275/40 R19 -1.3% -1.3% ✓ OK
225/60 R17 -1.4% -1.4% ✓ OK
225/65 R17 +1.7% +1.7% ✓ OK
225/65 R16 -1.9% -1.9% ✓ OK

Compare sizes

Looks valid
Looks valid
Units
✓ Within toleranceDiameter -0.0% (-0.01 in) · US (~3%)
  • Within tolerance · Diameter -0.0%.
  • Speedo @ 60: 60 mph60.0 mph.
  • Sidewall +1.50 in · Width -0.79 in.
Diameter-0.0%-0.01 in
Speedo @ 60-0.0%60 mph60.0 mph
Sidewall+1.50 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
28.04 in 28.03 in-0.01 in
Sidewall
4.52 in 6.01 in+1.50 in
Width
10.04 in 9.25 in-0.79 in
Circumference
88.08 in 88.05 in-0.0%
Revs / mile
719 720
Speedo @ 60
60 mph 60.0 mph-0.0%
Δ⌀ −0.2 mm
  • Current255/45 R19
  • New235/65 R16
  • Grounded to the road: the axle rises -0.00 in.

Result report

255/45 R19 235/65 R16 · Within tolerance

Use this size when shopping: 235/65 R16

Use this size when shopping

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

Safe alternative sizes

SizeDiameterSpeedo @ 100Use this
−1″ 255/50R18+0.0%+0.0%
OE 255/45R19+0.0%+0.0%
+1″ 255/40R20-0.0%-0.0%
+2″ 255/35R21-0.0%-0.0%

More tools

Last reviewed: 2026-06-28

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