Wheel Offset vs Backspacing Guide
Offset and backspacing describe where a wheel sits inside the wheel opening. They are related measurements, but they are not the same thing.
What is wheel offset?
Offset is the distance between the wheel’s mounting surface and the wheel’s centerline. It is usually expressed in millimeters.
- Positive offset: the mounting surface is toward the street-facing side of the wheel, generally moving more of the wheel inward.
- Zero offset: the mounting surface is at the wheel centerline.
- Negative offset: the mounting surface is toward the back side of the wheel, generally moving more of the wheel outward.
What is backspacing?
Backspacing is the distance from the wheel mounting surface to the inner edge of the wheel. It is commonly expressed in inches.
Why both matter
Two wheels with the same diameter can sit very differently if their width, offset or backspacing changes. Too much inward position can create interference with suspension, steering or brakes. Too much outward position can cause tire or wheel contact with the fender or body.
Wheel width changes the relationship
Offset cannot be evaluated by itself because changing wheel width changes where the inner and outer edges sit. Always evaluate diameter, width, offset/backspacing and the tire as one complete package.
Deep-dish appearance
A deeper outer lip can be associated with lower or negative offsets on some wheel designs, but appearance alone does not tell you whether a wheel fits a specific car. Brake, hub, suspension and body clearances still need to be verified.
Before ordering
Confirm your vehicle’s exact configuration and any suspension, brake, axle, spacer or adapter changes. When possible, compare measurements from a wheel that already fits the vehicle.
Start with the Fitment Center, review How to Measure Bolt Pattern, or send us your vehicle details and photos.