265/50 R20

What size is 265/50 R20?

265/50 R20 has an overall diameter of about 30.43 in, a section width of 10.43 in and a sidewall height of 5.22 in. It turns roughly 663 times per mile. Below are the exact figures plus in-tolerance plus/minus sizes you can switch to safely.

Fitment verdict

265/45 R21 stays within the configured tolerance for 265/50 R20: -0.1% diameter and -0.1% speedometer effect.

Metric This size: 265/50 R20 Alternative: 265/45 R21 Difference Verdict
Overall diameter 30.43 in 30.39 in -0.1% Within tolerance
Section width 10.43 in 10.43 in 0.00 in Computed difference
Sidewall height 5.22 in 4.69 in -0.52 in Computed difference
Circumference 95.61 in 95.47 in -0.1% Within tolerance
Speedo 0.0% -0.1% -0.1% 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 diameter30.43 in
Section width10.43 in
Sidewall height5.22 in
Circumference95.61 in
Revolutions 412 /km · 663 /mi

In-tolerance sizes

Alternative sizes that stay within the safe diameter tolerance:

Size Diameter Speedo Verdict
265/45 R21 -0.1% -0.1% ✓ OK
245/70 R17 +0.2% +0.2% ✓ OK
265/60 R18 +0.3% +0.3% ✓ OK
265/40 R22 -0.3% -0.3% ✓ OK
245/65 R18 +0.3% +0.3% ✓ OK
265/65 R17 +0.4% +0.4% ✓ OK
265/70 R16 +0.6% +0.6% ✓ OK
275/45 R21 +1.0% +1.0% ✓ OK
255/65 R17 -1.3% -1.3% ✓ OK
255/50 R20 -1.3% -1.3% ✓ OK
235/65 R18 -1.3% -1.3% ✓ OK
275/55 R19 +1.6% +1.6% ✓ OK

Compare sizes

Looks valid
Looks valid
Units
✓ Within toleranceDiameter -0.1% (-0.04 in) · US (~3%)
  • Within tolerance · Diameter -0.1%.
  • Speedo @ 60: 60 mph59.9 mph.
  • Sidewall -0.52 in · Width +0.00 in.
Diameter-0.1%-0.04 in
Speedo @ 60-0.1%60 mph59.9 mph
Sidewall-0.52 inWidth +0.00 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
30.43 in 30.39 in-0.04 in
Sidewall
5.22 in 4.69 in-0.52 in
Width
10.43 in 10.43 in+0.00 in
Circumference
95.61 in 95.47 in-0.1%
Revs / mile
663 664
Speedo @ 60
60 mph 59.9 mph-0.1%
Δ⌀ −1.1 mm
  • Current265/50 R20
  • New265/45 R21
  • Grounded to the road: the axle rises -0.02 in.

Result report

265/50 R20 265/45 R21 · Within tolerance

Use this size when shopping: 265/45 R21

Use this size when shopping

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

Safe alternative sizes

SizeDiameterSpeedo @ 100Use this
−1″ 265/55R19+0.1%+0.1%
OE 265/50R20+0.0%+0.0%
+1″ 185/65R21+0.1%+0.1%
+2″ 165/65R22+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.