Hub-Centric Ring Calculator
The ring’s outside matches the wheel. The inside matches the hub. It does not move the lug holes.
- The outer circle is the wheel centre bore. The inner circle is the hub.
- Radial wall is half the difference. Matching bores need no ring.
- If the wheel is smaller than the hub, it will not go on. A ring does not change PCD.
What it does
Subtracts hub diameter from wheel centre bore. If the wheel is larger, the ring OD is the wheel bore, ID is the hub, radial thickness is half the difference. Equal bores need no ring. A wheel smaller than the hub will not go on.
How to use it
Enter hub bore (mm) from Vehicle Fit or a measurement, and the wheel’s centre bore from the wheel listing. Spelling on OEM data is often centre_bore.
How to read the result
A hub-centric wheel centers on the hub, not the lugs. Lug-centric wheels can still be dangerous if they are not centered while you torque. Rings are usually plastic or aluminum. They are not a PCD adapter.
What this does not calculate
We size the ring. We do not know material, thickness of the hub pad, or whether that wheel is actually hub-centric.
Does not change 5x112 into 5x114.3. Use Bolt pattern for that — those two are not the same.
Questions
- Where do I find my hub bore?
- Vehicle Fit lists centre bore for almost every vehicle in our table. You can also measure the hub flange with a caliper.
- Will a ring fix vibration?
- It can if the wheel was hanging on the lugs. It will not fix a bent rim or a balance problem.
Related tools
- Free Bolt Pattern Converter — 5x114.35x114.3 mm is 5x4.5". 5x112 is not. Close is not a fit.
- Wheel Spacer CalculatorA spacer pushes the wheel out. On slip-on hardware it also eats stud thread. Measure; do not guess.
- Free Wheel Offset CalculatorMore positive offset tucks the wheel in. More width with the same offset pokes both ways.
- Vehicle FitLook up bolt pattern, offset, center bore and factory wheel specs by year, make and model.
Estimate — not a fitment approval.
