305/45 R22

What size is 305/45 R22?

305/45 R22 has an overall diameter of about 32.81 in, a section width of 12.01 in and a sidewall height of 5.40 in. It turns roughly 615 times per mile. Below are the exact figures plus in-tolerance plus/minus sizes you can switch to safely.

Fitment verdict

33x12.50 R15 stays within the configured tolerance for 305/45 R22: +0.6% diameter and +0.6% speedometer effect.

Metric This size: 305/45 R22 Alternative: 33x12.50 R15 Difference Verdict
Overall diameter 32.81 in 33.00 in +0.6% Within tolerance
Section width 12.01 in 12.50 in +0.49 in Computed difference
Sidewall height 5.40 in 9.00 in +3.60 in Computed difference
Circumference 103.07 in 103.67 in +0.6% Within tolerance
Speedo 0.0% +0.6% +0.6% 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 diameter32.81 in
Section width12.01 in
Sidewall height5.40 in
Circumference103.07 in
Revolutions 382 /km · 615 /mi

In-tolerance sizes

Alternative sizes that stay within the safe diameter tolerance:

Size Diameter Speedo Verdict
33x12.50 R15 +0.6% +0.6% ✓ OK
33x12.50 R16 +0.6% +0.6% ✓ OK
33x12.50 R18 +0.6% +0.6% ✓ OK
285/65 R18 -0.7% -0.7% ✓ OK
275/70 R18 +1.1% +1.1% ✓ OK
285/45 R22 -2.2% -2.2% ✓ OK
275/65 R18 -2.2% -2.2% ✓ OK
275/55 R20 -2.7% -2.7% ✓ OK

Compare sizes

Looks valid
Looks valid
Units
✓ Within toleranceDiameter +0.6% (+0.19 in) · US (~3%)
  • Within tolerance · Diameter +0.6%.
  • Speedo @ 60: 60 mph60.4 mph.
  • Sidewall +3.60 in · Width +0.49 in.
Diameter+0.6%+0.19 in
Speedo @ 60+0.6%60 mph60.4 mph
Sidewall+3.60 inWidth +0.49 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
32.81 in 33.00 in+0.19 in
Sidewall
5.40 in 9.00 in+3.60 in
Width
12.01 in 12.50 in+0.49 in
Circumference
103.07 in 103.67 in+0.6%
Revs / mile
615 611
Speedo @ 60
60 mph 60.4 mph+0.6%
Δ⌀ +4.9 mm
  • Current305/45 R22
  • New33x12.50 R15
  • Grounded to the road: the axle rises +0.10 in.

Result report

305/45 R22 33x12.50 R15 · Within tolerance

Use this size when shopping: 33x12.50 R15

Use this size when shopping

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

Safe alternative sizes

SizeDiameterSpeedo @ 100Use this
−1″ 215/70R21+0.1%+0.1%
OE 305/45R22+0.0%+0.0%
+1″ 355/35R23-0.1%-0.1%
+2″ 225/50R24+0.2%+0.2%

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.