Compare two wheel setups and calculate how changes in wheel width and offset (ET) affect inner clearance, outer position (poke), and track width. Ideal for choosing aftermarket wheels and checking whether a new setup will fit your vehicle.
✔ Compare wheel fitment • ✔ Offset changes • ✔ Inner & outer clearance • ✔ Instant results
Changing wheel width or offset affects suspension clearance, wheel arch clearance, handling characteristics, and the vehicle's overall stance.
Wheel offset (often marked as ET) is the distance between the wheel's mounting face and its centreline. It determines how far the wheel sits inside or outside the wheel arch.
This calculator calculates:
Current wheel:
7.5J ET45
New wheel:
8.5J ET35
The new wheel sits approximately:
Incorrect wheel offset can affect:
ET stands for the German word Einpresstiefe, meaning wheel offset.
Yes. Lower offset pushes the wheel further outward, giving the vehicle a wider stance.
Large offset changes may cause tyre rubbing, increased bearing wear, altered steering geometry, or suspension interference.
No. Wheel width also changes the inner and outer wheel position, so both measurements should always be considered together.
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Last Updated: August 2026