Section Width505 mm (19.9")
Aspect Ratio12%
Rim Diameter30"
Overall Diameter883 mm (34.8")
Sidewall Height61 mm
Circumference2775 mm
505/12R30 — Buy Tires

Everything to know about the 505/12R30 tire size

Size geometry

A 505/12R30 tire has a 505mm section width and a 12% aspect ratio, mounted on a 30-inch rim. Sidewall height works out to 60.6mm (2.39") and overall outside diameter is 883.2mm (34.77"). At highway speed the tire completes about 360 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 505/12R30 is unavailable, the closest same-diameter substitutes on the same rim are 495/12R30 and 515/12R30. 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 505/12R30 you can upsize to 515/9R31 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 495/15R29 (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 505/12R30 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 505/12R30

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