235/50R19 vs 245/45R20Tire Size Comparison

Safe

The 1.5% diameter difference is within the accepted 3% tolerance.

235/50R19718mm dia245/45R20729mm dia+5.4mm

Comparison Details

Overall Diameter717.6 vs 728.5 mm (+10.9 mm)
Diameter Difference+1.52%
Section Width235 vs 245 mm (+10 mm)
Sidewall Height117.5 vs 110.3 mm (-7.2 mm)
Circumference2254.4 vs 2288.7 mm
Clearance Change+5.4 mm
Speedometer Error+1.52%
Revs/Mile714 vs 703

Speedometer Correction

When switching from 235/50R19 to 245/45R20, 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/h101.5 km/h+1.5 km/h
110 km/h111.7 km/h+1.7 km/h
120 km/h121.8 km/h+1.8 km/h
130 km/h132.0 km/h+2.0 km/h

Vehicles Using These Sizes

Vehicles with 235/50R19

2025 Hyundai TucsonLimited/N Line2024 Hyundai TucsonLimited/N Line2023 Hyundai TucsonLimited/N Line2022 Hyundai TucsonN Line

Vehicles with 245/45R20

2023 Chrysler 300300S2024 Dodge ChargerR/T/Scat Pack2023 Dodge ChargerR/T/Scat Pack2022 Dodge ChargerR/T/Scat Pack2021 Dodge ChargerR/T/Scat Pack2020 Dodge ChargerR/T/Scat Pack2026 Ford EscapePlatinum (20")

Practical Guidance

Switching from 235/50R19 to 245/45R20 is within the industry-accepted 3% diameter tolerance. Your speedometer, ABS, and traction control should function normally. Note: these sizes require different rim diameters (19" vs 20"), so you will need different wheels.

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 1.52%, width changes by 10mm.

Speedometer error will be 1.52%. At an indicated 100 km/h, actual speed is about 101.5 km/h.

Ground clearance changes by +5.4mm per side.