Section Width645 mm (25.4")
Aspect Ratio47%
Rim Diameter12"
Overall Diameter911 mm (35.9")
Sidewall Height303 mm
Circumference2862 mm
645/47R12 — Buy Tires

Everything to know about the 645/47R12 tire size

Size geometry

A 645/47R12 tire has a 645mm section width and a 47% aspect ratio, mounted on a 12-inch rim. Sidewall height works out to 303.1mm (11.94") and overall outside diameter is 911.1mm (35.87"). At highway speed the tire completes about 349 revolutions per kilometre — your speedometer and odometer were calibrated against this number.

Direct substitute sizes

If 645/47R12 is unavailable, the closest same-diameter substitutes on the same rim are 635/48R12 and 655/46R12. 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 645/47R12 you can upsize to 655/44R13 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 635/50R11 (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 645/47R12 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 645/47R12

tire_size.no_vehicles_found