A Complete Guide to Understanding Rim Size, Fitment, and Offset

A Complete Guide to Understanding Rim Size, Fitment, and Offset

Must Take Steps When Buying Rims

When it comes to upgrading your vehicle's rims, understanding the specifics of rim size, fitment, and offset is crucial. These factors not only affect your vehicle's aesthetics but also its performance and safety. At R&T Sales Limited, we're here to help you navigate these terms and make the best decision for you. So, let's dive in!

What is Rim Size?

Rim size refers to the diameter and width of the wheel. It’s usually expressed in inches. For example, a rim size might be listed as 17x8, which means the rim has a diameter of 17 inches and a width of 8 inches.


  • The diameter of the rim is the distance across the rim, measured through the center.
  • This measurement impacts the overall height of the tire, affecting your vehicle's ground clearance and handling.


  • The width of the rim is the distance from one edge to the other.
  • It influences the tire's contact patch, which affects traction and handling.

Understanding Fitment

Fitment is all about ensuring the wheels you choose will fit your vehicle correctly without rubbing against the body or suspension components. Proper fitment involves considering the following:

Bolt Pattern

  • The bolt pattern is the arrangement of the lug holes on the wheel.
  • It’s usually shown in a format like “5x114.3”, which means 5 lug holes with a diameter of 114.3mm.

Center Bore

  • The centre bore is the hole in the middle of the wheel that fits over the hub.
  • A correct match ensures the wheel is centred on the hub, providing a smooth ride.

Decoding Offset

Offset is the distance from the wheel's mounting surface to the centerline of the wheel. It’s crucial for ensuring your wheels align correctly with your vehicle's suspension and bodywork. Check out the offset calculator on the Resources page!

Types of Offset

Positive Offset: The mounting surface is closer to the front (road side) of the wheel. This is common in most modern vehicles.

Negative Offset: The mounting surface is closer to the back (brake side) of the wheel, giving a deep-dish appearance.
Zero Offset: The mounting surface is exactly in the centre of the wheel.

Image obtained from https://www.reddit.com/r/coolguides/comments/161o063/a_cool_guide_to_wheel_offsets_on_cars/

Impact of Offset

  • Correct offset ensures your wheels don’t stick out too far or sit too far inside the wheel wells.
  • Improper offset can lead to poor handling, excessive wear on suspension components, and potential safety issues.

    Why It All Matters

    Choosing the right rim size, fitment, and offset is essential for several reasons:

    Performance: Properly fitted wheels improve handling and traction.
    Safety: Ensuring the wheels fit correctly avoids rubbing, which can damage tires and suspension components.
    Aesthetics: The right size and offset ensure your wheels complement your vehicle's look without sticking out awkwardly or sitting too far inside the wheel wells.

      R&T Sales Limited: Your Go-To for Wheel Upgrades

      At R&T Sales Limited, we understand the complexities of wheel upgrades. If you have questions, we provide a text service that connects you with our sales team. All questions will be answered, and a quote provided- right to your fingertips.

      1) Find your perfect rims today by shopping now. Can’t find what you’re looking for? We can source or customize any rim to meet your needs.
      2) Add your products to a quote and let us do the rest of the work.

      Our quote system allows us to provide you with the best pricing, confirm the products will fit your vehicle, and give the best shipping option (if required) for efficient delivery.

      Ready to elevate your ride? Visit us in store, online, or text us today for the best wheels and expert advice.


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