Comparison
225/40 R18 vs 245/35 R18
Stepping from 225/40 R18 to 245/35 R18 keeps the 18-inch wheel but widens the section by 20 mm. This setup keeps overall diameter very close to stock. Expect a more planted steering feel, at the cost of some of the cushioning a taller sidewall provides.
Speedometer drift stays small enough that most drivers won't notice it day to day. Diameter change stays inside the conservative ±3% safety window — an OEM-safe fitment on most vehicles.
TakeReasonable performance-leaning swap as long as fender and suspension clearance check out.
Quick math: 245/35 R18 is 8.5 mm shorter than 225/40 R18, shifting the speedometer by -1.33%.
Current Tire
New Tire
Ground line · scaled comparison
Excellent Fit
Within ±3% — safe for daily driving
Diameter change
-8.5 mm
-1.33%
Speedometer at 100
98.7 km/h
-1.33% error
Ground clearance
-4.3 mm
ride height delta
Sidewall change
-4.3 mm
revs/km: 506.3
Permalink for this comparison:
/compare/225-40-r18-vs-245-35-r18Detailed comparison
| Metric | 225/40 R18 | 245/35 R18 | Difference |
|---|---|---|---|
| Overall diameter | 637.2 mm | 628.7 mm | -8.5 mm (-1.33%) |
| Sidewall height | 90.0 mm | 85.8 mm | -4.3 mm |
| Circumference | 2.002 m | 1.975 m | -26.7 mm |
| Revs / km | 499.5 | 506.3 | +6.8 |
| Ground clearance | reference | -4.3 mm | -4.3 mm |
| Speedometer @ 100 km/h | 100.0 km/h | 98.7 km/h | -1.33 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 98.7 km/h after switching to 245/35 R18 — a -1.33% 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 -4.3 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
225/40 R18
Back to
245/35 R18
Drivers also compare
Closely-related fitments and plus-size swaps for 225/40 R18 and 245/35 R18.
215/40 R18 vs 245/35 R18
Wider variation on the same rim — more grip, less clearance.
Δ 0.08%
225/40 R18 vs 255/35 R18
Wider variation on the same rim — more grip, less clearance.
Δ 0.24%
245/35 R18 vs 255/35 R18
Wider variation on the same rim — more grip, less clearance.
Δ 1.11%
225/40 R18 vs 235/40 R18
Wider variation on the same rim — more grip, less clearance.
Δ 1.26%
215/40 R18 vs 225/40 R18
Wider variation on the same rim — more grip, less clearance.
Δ 1.27%
225/40 R18 vs 275/35 R18
Wider variation on the same rim — more grip, less clearance.
Δ 1.96%
215/45 R18 vs 225/40 R18
Wider variation on the same rim — more grip, less clearance.
Δ 2.07%
225/40 R18 vs 245/40 R18
Wider variation on the same rim — more grip, less clearance.
Δ 2.51%
Related topics