So you’ve decided to update the rim’s on your car? All you need to know is the bolt pattern of your car so you can find a set of wheels that will fit properly.

The phrase ‘Bolt Pattern’ (or lug pattern, bolt circle, lug spacing, etc.) refers to the diameter of an imaginary circle formed by the centers of the lugs on your automobile’s wheel and consists of two numbers and looks like this: 5×4.50. The first number in this example (5) indicates how many lugs are on the vehicle, the other number (4.50) describes the diameter of the circle formed by those 5 lugs.

Lug patterns can be described in either inch or millimeter units (4.50 is inches). Bolt pattern diameters are most commonly in the range of 4-6 inches (100-150 millimeters).

**The 2 Steps to Measuring Your Bolt Pattern**

**One)** Count the number of lugs on your wheel. Most vehicles have 4, 5 or 6 lugs.

**Two)** Measure the Diameter.

If you have 4, 6 or 8 lugs, measure the center-to-center distance between two lugs that are directly across the hub from each other. That measurement is your diameter.

If you have 5 or 7 lugs, you will have to take one more step, and you’ll need a calculator.

For 5 lugs, measure the center-to-center distance between two studs that are not side-by-side. Now multiply your measurement by 1.05 to get the diameter.

If there are 7 lugs, measure the center-to-center distance between two studs that are approximately across the hub from each other. Multiply your measurement by 1.03.

Because of the multiplication involved, it’s easier to measure 5 or 7 lug patterns in millimeters.