Section Width425 mm (16.7")
Aspect Ratio49%
Rim Diameter18"
Overall Diameter874 mm (34.4")
Sidewall Height208 mm
Circumference2745 mm
425/49R18 — Buy Tires

Everything to know about the 425/49R18 tire size

Size geometry

A 425/49R18 tire has a 425mm section width and a 49% aspect ratio, mounted on a 18-inch rim. Sidewall height works out to 208.3mm (8.20") and overall outside diameter is 873.7mm (34.40"). At highway speed the tire completes about 364 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 425/49R18 is unavailable, the closest same-diameter substitutes on the same rim are 415/50R18 and 435/48R18. Both keep your speedometer reading within 1% — safe for daily use, ABS, and stability control. Always verify load and speed ratings before swapping.

Plus / minus sizing options

For a 425/49R18 you can upsize to 435/45R19 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 415/53R17 (minus-one) for a softer ride or winter setup. Both stay inside the Âą3% diameter tolerance that ABS and TPMS systems expect.

Vehicle compatibility

0 vehicles in our database run the 425/49R18 tire size from the factory. Aftermarket fitment depends on rim width, offset, and clearance — match these specs to your wheel before purchasing tires.

Vehicles Using 425/49R18

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