Section Width285 mm (11.2")
Aspect Ratio42%
Rim Diameter20"
Overall Diameter747 mm (29.4")
Sidewall Height120 mm
Circumference2348 mm
285/42R20 — Buy Tires

Everything to know about the 285/42R20 tire size

Size geometry

A 285/42R20 tire has a 285mm section width and a 42% aspect ratio, mounted on a 20-inch rim. Sidewall height works out to 119.7mm (4.71") and overall outside diameter is 747.4mm (29.43"). At highway speed the tire completes about 426 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 285/42R20 is unavailable, the closest same-diameter substitutes on the same rim are 275/44R20 and 295/41R20. 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 285/42R20 you can upsize to 295/36R21 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 275/48R19 (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 285/42R20 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 285/42R20

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