Section Width945 mm (37.2")
Aspect Ratio21%
Rim Diameter27"
Overall Diameter1083 mm (42.6")
Sidewall Height198 mm
Circumference3401 mm
945/21R27 — Buy Tires

Everything to know about the 945/21R27 tire size

Size geometry

A 945/21R27 tire has a 945mm section width and a 21% aspect ratio, mounted on a 27-inch rim. Sidewall height works out to 198.4mm (7.81") and overall outside diameter is 1082.7mm (42.63"). At highway speed the tire completes about 294 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 945/21R27 is unavailable, the closest same-diameter substitutes on the same rim are 935/21R27 and 955/21R27. 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 945/21R27 you can upsize to 955/19R28 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 935/23R26 (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 945/21R27 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 945/21R27

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