Hub Centric Ring Size Calculator
Determine the exact ring size needed to perfectly center your aftermarket wheels.
Required Hub Centric Ring Size
The ring’s Inner Diameter (ID) must match the Vehicle Hub Bore, and the Outer Diameter (OD) must match the Wheel Center Bore.
What is a Hub Centric Ring?
A hub centric ring is a small but crucial component used when installing aftermarket wheels onto a vehicle. These rings, also known as spigot rings or center rings, are designed to fill the gap between the vehicle’s wheel hub and the center bore of the wheel. Most aftermarket wheels are manufactured with a large center bore to fit a wide variety of vehicles. Our hub centric ring size calculator helps you find the precise ring needed to bridge this size difference. When this gap isn’t filled, the wheel is only centered by the lug nuts (a “lug-centric” fit), which can lead to vibrations, uneven tire wear, and a less safe connection.
Anyone installing non-original equipment (aftermarket) wheels should use this hub centric ring size calculator. A common misconception is that hub centric rings bear the vehicle’s weight. In reality, their sole purpose is to perfectly center the wheel on the hub during installation. The clamping force from the tightened lug nuts is what actually holds the wheel securely and bears the load.
Hub Centric Ring Formula and Mathematical Explanation
The calculation for determining the correct hub centric ring size is straightforward. There isn’t a complex mathematical formula, but rather a direct matching of two key measurements. The goal of the hub centric ring size calculator is to identify a ring that perfectly adapts the wheel’s bore to the vehicle’s hub.
- Ring Inner Diameter (ID) = Vehicle’s Hub Bore Diameter
- Ring Outer Diameter (OD) = Wheel’s Center Bore Diameter
For example, if your vehicle’s hub measures 66.6 mm and your new wheels have a center bore of 73.1 mm, you need a hub centric ring specified as 73.1 mm OD / 66.6 mm ID. Our hub centric ring size calculator performs this matching for you instantly.
| Variable | Meaning | Unit | Typical Range |
|---|---|---|---|
| Vehicle Hub Bore | The diameter of the raised lip on the vehicle’s wheel hub. | mm | 54.1 – 110+ mm |
| Wheel Center Bore | The diameter of the large central hole in the back of the wheel. | mm | 60.1 – 110+ mm |
| Ring ID (Inner Diameter) | The inside measurement of the hub ring; must match the vehicle hub. | mm | Matches Vehicle Hub Bore |
| Ring OD (Outer Diameter) | The outside measurement of the hub ring; must match the wheel bore. | mm | Matches Wheel Center Bore |
Practical Examples (Real-World Use Cases)
Example 1: Fitting Aftermarket Wheels to a BMW
A user owns a BMW with a standard hub bore of 72.6 mm. They purchase a set of aftermarket wheels that have a center bore of 74.1 mm. By entering these values into the hub centric ring size calculator:
- Input 1 (Vehicle Hub): 72.6 mm
- Input 2 (Wheel Bore): 74.1 mm
- Calculator Output: The required ring size is 74.1 / 72.6 mm. This simple device prevents high-speed vibrations. For more information on fitment, see our article on what are hub centric rings.
Example 2: Upgrading a Honda Civic’s Wheels
An owner of a Honda Civic wants to install new wheels. The Civic’s hub bore is 64.1 mm. The desired wheels have a common center bore of 73.1 mm to fit multiple cars. Using the hub centric ring size calculator is essential here.
- Input 1 (Vehicle Hub): 64.1 mm
- Input 2 (Wheel Bore): 73.1 mm
- Calculator Output: A 73.1 / 64.1 mm ring is needed. Without it, the wheel would not be properly centered, potentially causing a shaky ride. Understanding how to measure wheel bore is a key first step.
How to Use This Hub Centric Ring Size Calculator
- Measure Your Vehicle’s Hub Bore: Use a digital caliper for the most accurate measurement of the hub lip on your car. This is your “Inner Diameter” (ID). Enter this value into the first field of the hub centric ring size calculator.
- Measure Your Wheel’s Center Bore: Measure the large central opening on the back of your aftermarket wheel. This is your “Outer Diameter” (OD). Input this into the second field.
- Read the Results: The calculator will instantly display the required ring size, showing both the inner and outer diameters you need to purchase. It also visualizes the measurements for easy comparison.
- Decision-Making: The result is not a suggestion; it is the exact size required for a “hub-centric” fit. Using a ring of the correct size is critical for safety and ride quality. If you’re unsure, our guide on spigot rings explained can help.
| Manufacturer | Common Hub Bore (mm) |
|---|---|
| Subaru | 56.1 |
| Toyota / Lexus | 60.1 |
| Honda / Acura | 64.1 |
| Nissan / Infiniti | 66.1 |
| Audi / VW / Mercedes | 57.1 or 66.6 |
| Mazda / Hyundai / Kia / Mitsubishi | 67.1 |
| BMW | 72.6 or 74.1 |
| Ford / Dodge (Trucks) | 87.1 / 93.1 / 106.1 |
Key Factors That Affect Hub Centric Ring Fitment
While the hub centric ring size calculator simplifies finding the right size, several factors influence their effectiveness.
- Material: Rings are typically made from durable plastic (polycarbonate) or aluminum. Plastic rings are resistant to corrosion and are perfectly adequate, as they don’t bear any load. Aluminum rings offer higher heat resistance but can sometimes corrode and seize to the hub or wheel.
- Manufacturing Tolerance: High-quality rings are made with very tight tolerances. A poorly made ring might be too loose or too tight, defeating its purpose. It’s crucial to buy from reputable brands.
- Correct Measurement: The most common error is incorrect measurement. Using a ruler is not precise enough; digital calipers are required for accuracy to a fraction of a millimeter, which is vital for the hub centric ring size calculator to work. Any issues here can lead to vibration after new wheels.
- Hub Condition: The vehicle’s hub must be clean and free of rust or debris before installing the ring. Any obstruction can prevent the ring and wheel from seating flush against the hub.
- Wheel Design: Ensure the back of the wheel’s mounting pad has a chamfer (a slight bevel) that allows the hub ring to sit correctly. Most quality wheels do, but it’s worth checking.
- Installation: The ring should slide onto the vehicle hub snugly by hand. If it requires force, something is wrong. Similarly, it should fit securely into the back of the wheel. Considering wheel spacers vs hub rings is another part of the fitment puzzle.
Frequently Asked Questions (FAQ)
Yes, if your aftermarket wheels have a center bore larger than your vehicle’s hub. They are essential for centering the wheel properly to prevent vibrations and ensure a safe fit. Our hub centric ring size calculator helps you find the right ones.
Both work well. Plastic (polycarbonate) rings are most common; they don’t corrode and are more than strong enough since they don’t bear any load. Metal (aluminum) rings are more durable but can sometimes seize to the hub due to corrosion.
You risk experiencing vibrations, especially at highway speeds. The wheels will be “lug-centric,” meaning they are centered only by the lug nuts, which is less precise and can lead to uneven tire wear and stress on the wheel studs over time.
Absolutely. A ring that is too small won’t fit over the hub. A ring that is too loose (either on the ID or OD) will not center the wheel properly, causing the very vibrations you’re trying to prevent.
The most reliable method is to measure it directly with a digital caliper. You can also search for your vehicle’s specifications online or consult the table in this article, but physical measurement is always recommended before using the hub centric ring size calculator.
No. Factory wheels are designed to be hub-centric for your specific vehicle from the manufacturer, so their center bore already matches the hub diameter perfectly.
No, this is a common myth. The ring is purely an alignment tool. The weight of the vehicle is supported by the friction and clamping force between the wheel, hub, and tightened lug nuts.
Yes, as long as they are not cracked, deformed, or damaged. When you get new wheels, you will need to check if the center bore is the same. If it’s different, you will need a new set of rings, which you can determine with our hub centric ring size calculator.