What is wheel offset?
Wheel offset is the distance, in millimeters, between the wheel’s true centerline and its mounting face (the surface that bolts to the hub). A positive offset pulls the wheel’s face toward the outside of the vehicle (common on most modern front-wheel-drive cars); a negative offset pushes it toward the suspension, making the wheel poke further out.
How this calculator works
This tool converts backspacing (the distance from the mounting face to the back edge of the wheel) and wheel width into offset, using: Offset (mm) = [Backspacing (in) − (Wheel Width (in) ÷ 2)] × 25.4. It also calculates the front face distance, showing how far the outer lip sits from the hub.
Wheel offset and backspacing are related but different measurements, and manufacturers list one or the other depending on the market — this calculator lets you move between them. Getting offset wrong can cause tire rub, altered scrub radius, or bearing stress, so always confirm fitment against your vehicle’s suspension clearance and manufacturer specs.
This calculator is for general reference and planning purposes only.