Practical tools for measured work
Wheel Spacer Calculator
See how a wheel spacer changes your effective offset and how far the wheel moves outward.
How it works
A spacer sits between the hub and the wheel, pushing the wheel outward by exactly its thickness. Effective offset = original offset − spacer thickness. This moves the wheel face outward and pulls the inner barrel away from suspension and brake components by the same amount.
Worked example: a 10 mm spacer changes an ET45 wheel to an effective ET35. The inner wheel face gains 10 mm of clearance and the outer face moves 10 mm closer to the fender.
Limitations
This does not check for wheel-stud engagement length, hub-centric fit, or fender clearance - verify those separately.
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