225/55R18 vs 235/55R18Tire Size Comparison

Safe

The 1.6% diameter difference is within the accepted 3% tolerance.

225/55R18705mm dia235/55R18716mm dia+5.5mm

Comparison Details

Overall Diameter704.7 vs 715.7 mm (+11.0 mm)
Diameter Difference+1.56%
Section Width225 vs 235 mm (+10 mm)
Sidewall Height123.8 vs 129.3 mm (+5.5 mm)
Circumference2213.9 vs 2248.4 mm
Clearance Change+5.5 mm
Speedometer Error+1.56%
Revs/Mile727 vs 716

Speedometer Correction

When switching from 225/55R18 to 235/55R18, your speedometer will differ from actual speed.

SpeedometerActual SpeedDifference
30 km/h30.5 km/h+0.5 km/h
40 km/h40.6 km/h+0.6 km/h
50 km/h50.8 km/h+0.8 km/h
60 km/h60.9 km/h+0.9 km/h
70 km/h71.1 km/h+1.1 km/h
80 km/h81.2 km/h+1.2 km/h
90 km/h91.4 km/h+1.4 km/h
100 km/h101.6 km/h+1.6 km/h
110 km/h111.7 km/h+1.7 km/h
120 km/h121.9 km/h+1.9 km/h
130 km/h132.0 km/h+2.0 km/h

Vehicles Using These Sizes

Vehicles with 225/55R18

2025 Audi A6Premium 45 TFSI2024 Audi A6Premium 45 TFSI2023 Audi A6Premium 45 TFSI2022 Audi A6Premium 45 TFSI2021 Audi A6Premium 45 TFSI2020 Audi A6Premium 45 TFSI2025 Buick Encore GXSport Touring2025 Buick Encore GXAvenir2024 Buick Encore GXSport Touring2024 Buick Encore GXAvenir2023 Buick Encore GXAvenir2022 Buick Encore GXEssence2021 Buick Encore GXEssence2020 Buick Encore GXEssence2021 Hyundai TucsonSport/Limited/Ultimate2020 Hyundai TucsonSport/Limited/Ultimate2021 Mitsubishi OutlanderES2025 Mitsubishi Eclipse CrossES2024 Mitsubishi Eclipse CrossES2023 Mitsubishi Eclipse CrossES2022 Mitsubishi Eclipse CrossES2025 Subaru CrosstrekSport/Limited2024 Subaru CrosstrekSport/Limited2023 Subaru CrosstrekSport/Limited2022 Subaru CrosstrekSport/Limited2021 Subaru CrosstrekSport/Limited2020 Subaru CrosstrekLimited2025 Subaru ForesterSport/Limited/Touring2024 Subaru ForesterSport/Limited/Touring2023 Subaru ForesterSport/Limited/Touring2022 Subaru ForesterSport/Limited/Touring2021 Subaru ForesterSport/Limited/Touring2020 Subaru ForesterSport/Limited/Touring

Vehicles with 235/55R18

2025 Buick EnvisionSport Touring2025 Cadillac XT4Luxury2024 Cadillac XT4Luxury2023 Cadillac XT4Luxury2022 Cadillac XT4Luxury2023 Chrysler 300Touring2022 Chrysler 300Touring2021 Chrysler 300Touring2020 Chrysler 300Touring2025 Hyundai TucsonSEL/XRT2024 Hyundai TucsonSEL/XRT2023 Hyundai TucsonSEL/XRT2022 Hyundai TucsonSEL/Limited

Individual Tire Size Details

225/55R18
Full specifications, compatible vehicles, and alternatives
235/55R18
Full specifications, compatible vehicles, and alternatives

Practical Guidance

Switching from 225/55R18 to 235/55R18 is within the industry-accepted 3% diameter tolerance. Your speedometer, ABS, and traction control should function normally. Both sizes fit the same 18-inch rim, so no wheel change is needed.

The 3% diameter tolerance is a widely accepted industry guideline referenced by the ETRTO and most vehicle manufacturers. When in doubt, consult your vehicle's owner's manual or a qualified tire professional. For U.S. tire safety standards and recalls, see the NHTSA Tire Safety page.

Frequently Asked Questions

Safe. The overall diameter differs by 1.56%, width changes by 10mm.

Speedometer error will be 1.56%. At an indicated 100 km/h, actual speed is about 101.6 km/h.

Ground clearance changes by +5.5mm per side.