How To Measure Rim Size?

When evaluating rims, you must precisely take crucial measures. Determine whether a rim will fit on a car or tire by looking at its diameter, width, bolt pattern, offset or backspacing. Knowing whether to include or exclude a rim’s lips in the measurements is a crucial component. While offset, as well as backspacing measures, as well as backspacing measures, must always take the rim’s lips into account, width and diameter measurements must always ignore them. By accurately measuring a rim, you can fit the rim with tyres of the correct size. Always remove the tire and start taking the rim off of the tyre to just get accurate measurements.

Diameter of Center Hole:

Determine the diameter of a center hole by finding two spots that are exactly opposite one another and using a tape measure. (The diameter of the circle is always the greatest separation between any two locations near the edge of the circle.)

Bolt Holes’ Numbers:

Just counting the number of the bolt holes surrounding the central hole will allow you to identify this bolt design.

Bolt Hole Diameter:

To attach the rim and power your machine’s components, exact-sized bolts (or studs) will be used. With a tape measure, caliper, or by simply measuring the size of a bolt with such a nut whose size is known, the correct bolt holes diameter could be determined.

From One Bolt Hole Center to Another:

Measure the distance between the centers of the bolt holes on either side of you using a tape measure (either rotating clockwise or counterclockwise).

Rim Width and Diameter of Tires:

Using the size of the tyre is the simplest and most direct approach to determine the width as well as the diameter of a rim you’ll need. The rim will often be labeled to match the width as well as diameter of the suitable tyre, and it will be 1.5 inches narrower than your tyre in width.

Although acquiring the exact width and diameter might seem easy enough, it’s actually a frequent source of error. Of course, there are constantly edge circumstances.

How To Measure Rim Size?

You should not include either of the flanges in the width measurement in order to get an accurate reading. Measure the inner distance based on where the tyre will actually rest on the rim. Once more, consider where a tyre will sit while choosing the correct diameter. You should measure the diameter even without outside flanges in order to determine the height.

Rim Offset:

When viewed from the side, the mounting holes aren’t always vertically centered in the rim, even though the center hole and the circle formed by the bolt holes are (scroll for diagram). The mounting holes’ position in relation to the centerline of the wheel, whether forward or backward, determines the offset of the rim. The mounting holes could be offset positively (so that they are closer to the rim’s outer side), neutrally (so that they are in the center of the rim), or negatively (so that they are offset).

Since the width of the rim has already been established, finding the offset requires only measuring the distance between the outer border of the rim and the depth of the center disc. Measure down inside the rim to the middle plate with the rim lying on its side with the outside face facing up.

To measure this distance, you can use a tape measure and a straightedge, but make careful to ignore any bevels in the center disc and measure to the depth where the bolt holes are.

That’s all there is to it; with a few minutes as well as some straightforward measurements, you will have all of the information you need for your search. There are illustrations, places to indicate your measurements, and a review of measurements in our basic print guide, which you may download.

At H&R, we allow searching by make, model, and dimensions. If you experience any problems, get in touch with one of our Parts Specialists, who can assist you in exploring both our inventory and our global parts network.


It should be very obvious by this point that you can’t just guess at the right wheel size. Without the correct measurements, your fitment will pose a problem, whether you’re trying to achieve a staggered arrangement or simply need to replace your OEM rims that have been damaged.

Additionally, although you might only opt to use the stamped sizes listed at the hub’s back of your rim, they may not always include backspacing or offset, which are equally significant.

At first, it could seem a little intimidating, but after you’ve done it once or twice, it becomes much simpler.


What three measurements are used to calculate rim size?

When evaluating rims, you must precisely take 5 crucial measures. Determine whether a rim will fit on a car or tire by looking at its diameter, width, bolt pattern, offset and backspacing.

How can I make sure my rims and tyres will function together?

The two parameters that determine tyre and rim compatibility are width and diameter. You must ensure that the diameter of your tyres and wheels match exactly; for example, a 215/65R17 tyre will only fit on a wheel with a 17″ diameter.

On the same rim, is it possible to change the tyre size?

As long as the tyre and rims are the exact same internal diameter, you can alter the size of your tyres while keeping the same rims. However, because tyres are flexible, the width and height can be altered. When selecting tyres, be sure to pay close attention to the manufacturer’s specifications.

Any rim and any tyre will fit?

The wheel arrangement includes tires. For instance, even though the rims on your car are a specific size, you can buy alternative tire sizes to fit them as long as the middle of the tire is the right size. Having said that a car with larger rims will frequently be able to accommodate bigger tires than other cars.

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