Wheel Offset Calculator

Calculate backspacing, poke and offset (ET) for your wheels.

Formula

Backspacing = Wheel width (inches)/2 + Offset / ET (mm)/25,4 + 0,5 (in)

Assumptions

Assumption: a 0.5-inch flange allowance is added, matching most wheel-fitment calculators.

How to read it

A lower offset (ET) pushes the wheel outward (more poke); a higher offset tucks it toward the suspension. Compare backspacing with the space available on the strut side.

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