Section Width125 mm (4.9")
Aspect Ratio68%
Rim Diameter21"
Overall Diameter703 mm (27.7")
Sidewall Height85 mm
Circumference2210 mm
125/68R21 — Buy Tires

Everything to know about the 125/68R21 tire size

Size geometry

A 125/68R21 tire has a 125mm section width and a 68% aspect ratio, mounted on a 21-inch rim. Sidewall height works out to 85.0mm (3.35") and overall outside diameter is 703.4mm (27.69"). At highway speed the tire completes about 453 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 125/68R21 is unavailable, the closest same-diameter substitutes on the same rim are 115/74R21 and 135/63R21. 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 125/68R21 you can upsize to 135/54R22 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 115/85R20 (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 125/68R21 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 125/68R21

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