Section Width285 mm (11.2")
Aspect Ratio21%
Rim Diameter21"
Overall Diameter653 mm (25.7")
Sidewall Height60 mm
Circumference2052 mm
285/21R21 — Buy Tires

Everything to know about the 285/21R21 tire size

Size geometry

A 285/21R21 tire has a 285mm section width and a 21% aspect ratio, mounted on a 21-inch rim. Sidewall height works out to 59.9mm (2.36") and overall outside diameter is 653.1mm (25.71"). At highway speed the tire completes about 487 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 285/21R21 is unavailable, the closest same-diameter substitutes on the same rim are 275/22R21 and 295/20R21. 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 285/21R21 you can upsize to 295/16R22 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 275/26R20 (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 285/21R21 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 285/21R21

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