Comparison
245/45 R18 vs 265/35 R20
Plus-sizing from 245/45 R18 to 265/35 R20 keeps overall diameter close to factory while opening room for a larger 20-inch wheel. This sizing approach moves rolling diameter a touch off the original spec.
Expect a slight but noticeable shift in indicated speed compared to the original tires. Expect a more planted steering feel, at the cost of some of the cushioning a taller sidewall provides. Extra width broadens the footprint for more grip, but check inner liner and strut clearance before fitting. Many drivers pick this direction primarily for appearance — the bigger rim simply looks more aggressive. Overall the swap sits inside the safe ±3% diameter window, so ABS, traction control and gearing behave normally.
TakeCommon upgrade for sportier handling and a tighter wheel-gap look on the same vehicle.
Quick math: 265/35 R20 is 15.8 mm taller than 245/45 R18, shifting the speedometer by +2.33%.
Current Tire
New Tire
Ground line · scaled comparison
Excellent Fit
Within ±3% — safe for daily driving
Diameter change
+15.8 mm
2.33%
Speedometer at 100
102.3 km/h
+2.33% error
Ground clearance
+7.9 mm
ride height delta
Sidewall change
-17.5 mm
revs/km: 459.0
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/compare/245-45-r18-vs-265-35-r20Detailed comparison
| Metric | 245/45 R18 | 265/35 R20 | Difference |
|---|---|---|---|
| Overall diameter | 677.7 mm | 693.5 mm | +15.8 mm (+2.33%) |
| Sidewall height | 110.3 mm | 92.8 mm | -17.5 mm |
| Circumference | 2.129 m | 2.179 m | +49.6 mm |
| Revs / km | 469.7 | 459.0 | -10.7 |
| Ground clearance | reference | +7.9 mm | +7.9 mm |
| Speedometer @ 100 km/h | 100.0 km/h | 102.3 km/h | +2.33 km/h |
Verdict: excellent
Within ±3% — speedometer, ABS and traction control should behave normally.
Speedometer impact
At a true 100 km/h, your dashboard will read 102.3 km/h after switching to 265/35 R20 — a +2.33% offset. Use the speedometer error calculator to recheck for other indicated speeds, and the speedometer error guide for the full background.
Ground clearance change
The new tire's half-diameter changes ride height by +7.9 mm. Small differences are absorbed by suspension travel, but anything beyond ±10 mm can affect headlight aim, fender clearance and bump-stop margin. See the plus-sizing guide before committing.
Back to
245/45 R18
Back to
265/35 R20
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