What the tool checks
The PCD must be identical to the hub's: 5x112 will not fit on 5x114.3, even if the difference looks tiny. The centre bore of the wheel must be equal to or larger than the hub's; if it is larger, a hub centric ring fills the gap. The offset is compared with the original wheel of the same diameter, to the millimetre, on the suspension side and the wheel arch side (details in the offset calculator). The tyres suggested keep the original overall diameter to within 2 %, so the speedometer and driver aids stay accurate.
The result is for guidance only: brake caliper clearance, ride height and the approved fitments for your vehicle (certificate of conformity) still need checking. Have the fitting approved by a professional.
Frequently asked questions
How do I know if wheels will fit my car?
Four things must match: the PCD (number of holes and circle diameter, e.g. 5x112), the centre bore (equal to or larger than the hub, with a hub centric ring), the offset (ET) so the wheel rubs neither on the suspension nor on the wheel arch, and a tyre size with the same overall diameter as the original.
Can a wheel with a centre bore larger than my hub fit?
Yes, with a hub centric ring that fills the gap (for example 72.6 → 57.1 mm). It centres the wheel on the hub and prevents vibration. A wheel whose centre bore is smaller than the hub cannot be fitted without being re-bored by a professional.
Can I fit wheels with a different PCD?
Not directly. You need PCD adapters (for example 5x100 to 5x112), which also push the wheel out by a few tens of millimetres. Then check the resulting offset and that the fitting is compliant.
Do I need to change the nuts or bolts with aftermarket wheels?
Often, yes: original and aftermarket wheels don't always have the same seat shape (conical, spherical, flat) or the same thickness. Use the fixings intended for the wheel, with your vehicle's thread, and tighten to the manufacturer's torque.