Section Width135 mm (5.3")
Aspect Ratio21%
Rim Diameter21"
Overall Diameter590 mm (23.2")
Sidewall Height28 mm
Circumference1854 mm
135/21R21 — Buy Tires

Everything to know about the 135/21R21 tire size

Size geometry

A 135/21R21 tire has a 135mm section width and a 21% aspect ratio, mounted on a 21-inch rim. Sidewall height works out to 28.4mm (1.12") and overall outside diameter is 590.1mm (23.23"). At highway speed the tire completes about 539 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 135/21R21 is unavailable, the closest same-diameter substitutes on the same rim are 125/23R21 and 145/20R21. 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 135/21R21 you can upsize to 145/11R22 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 125/33R20 (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 135/21R21 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 135/21R21

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