Wheel Offset Calculator

How to Calculate Wheel Offset Changes

Understanding wheel offset changes is crucial when modifying your vehicle's wheels. This calculator helps you determine how changes in wheel width and offset affect the inner clearance and outer position of your wheels.

Wheel Offset Calculation Formulas

The following formulas are used in our wheel offset calculations:

1. Width Change: \[WidthChange = NewWidth - CurrentWidth\]
2. Offset Change: \[OffsetChange = NewOffset - CurrentOffset\]
3. Inner Clearance Change: \[InnerClearanceChange = \frac{WidthChange}{2} - OffsetChange\]
4. Outer Position Change: \[OuterPositionChange = \frac{WidthChange}{2} + OffsetChange\]

Calculation Steps

1. Calculate the change in wheel width
2. Calculate the change in wheel offset
3. Determine the change in inner clearance
4. Determine the change in outer position

Example Calculation

Let's calculate the changes when switching from a wheel with 7" width and 40mm offset to a wheel with 8" width and 35mm offset:

1. Convert measurements to mm:
   • Current Width: 7" × 25.4 = 177.8 mm
   • New Width: 8" × 25.4 = 203.2 mm
2. Calculate Width Change: \[WidthChange = 203.2 - 177.8 = 25.4 mm\]
3. Calculate Offset Change: \[OffsetChange = 35 - 40 = -5 mm\]
4. Calculate Inner Clearance Change: \[InnerClearanceChange = \frac{25.4}{2} - (-5) = 17.7 mm\]
5. Calculate Outer Position Change: \[OuterPositionChange = \frac{25.4}{2} + (-5) = 7.7 mm\]

In this example, the inner clearance increases by 17.7 mm, and the outer position moves out by 7.7 mm.

Wheel Offset Change Diagram

This diagram visually represents the changes in inner clearance and outer position based on the example calculation. It helps to easily compare the effects of changing wheel width and offset on your vehicle's wheel fitment.