Wheel Offset (ET) to Backspacing & Poke Calculator (Wheel Fitment)
Convert wheel offset (ET in millimeters) to backspacing (in inches) and calculate outer wheel poke and inner suspension clearance for aftermarket wheel fitment.
Wheel Backspacing (inches)
Calculator Inputs
Wheel Backspacing (inches)
Outer Wheel Poke toward Fender
Backspacing in Millimeters
Wheel Dimension Split: Backspacing vs Outer Poke (mm)
Standard custom wheel and automotive stance fitment calculation model.
This calculator is designed for educational and informational purposes based on publicly declared statutory frameworks. The outputs do not constitute binding financial, tax, or legal advice. We assume no liability for decisions made based on these estimates. Always verify with the relevant official authorities or a certified professional advisor.
Calculation Methodology
Total Rim Width = Nominal Width + 1.0 inch (for bead lips). Centerline (inches) = Total Width / 2. Backspacing (mm) = (Centerline * 25.4) + Offset ET. Backspacing (inches) = Backspacing (mm) / 25.4.
Frequently Asked Questions
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