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What Is Wheel Offset? [With Offset Chart]

Andrew Cilio
By: 

Andrew Cilio

 / Feb 20 2023
What Is Wheel Offset? [With Offset Chart]

Wheel offset is the distance of a wheel's mounting surface in relation to its centerline. This is measured in millimeters and relates to how far out or in a tire sits in the wheel well.

If you're thinking about upgrading your truck wheels or giving your ride a more aggressive stance, you might also be thinking about your wheel offset. But just what is wheel offset, and how does it relate to backspacing?

In this post, we'll explain in more detail how the space between a wheel's mounting surface and its centerline affects everything from backspacing to appearance to handling and everything in between—along with the pitfalls of taking offset a little too far.

Wheel Offset Explained

Wheel offset is technically defined as the distance between a wheel's mounting surface (the face where the wheel is bolted to the rotor's mounting surface) and its centerline (the lateral middle of the wheel). Understanding wheel offset is a vital part of understanding which wheel sizes and stances are on the table for your ride.

Graphic explaining what wheel offset is by showing the distance between the mounting surface and the centerline of a wheel

Positive vs. Negative Offset

Wheel offset can be categorized as either positive, negative, or zero/neutral, depending on where the mounting surface is set in relation to the centerline.

Positive Offset Wheels

When a wheel's mounting surface is closer to the outer lip of the wheel (right of centerline on a driver-side wheel if you're facing the front of a truck), the wheel has a positive offset. Since the wheel mounts to the rotor closer to the outer lip, more of the wheel will be housed deeper in the wheel well, so you won't see it poking out beyond the fender. Stock offset is usually positive.

Negative Offset Wheels

If a wheel's mounting surface lies closer to the inner lip of the wheel (left of centerline on a driver-side wheel if you're facing the front of a truck), it has a negative offset. Mounting a wheel closer to its inner lip means more of it will poke out beyond the fender, giving the truck a more aggressive stance.

Zero/Neutral Offset Wheels

Between a positive and negative offset is a zero or neutral offset. This happens when a wheel's mounting surface is aligned with the centerline in the middle of the barrel of the wheel. Wheels with zero offset will have a more flush fitment on most trucks, with the wheel's outer surface more or less aligned with the fender.

Graphic showing the three different types of wheel offsets, including positive, negative, and zero/netural.

How To Measure Wheel Offset

Want to see how much offset your wheel has? You should be able to find it in your owner's manual or the product description on the manufacturer's or seller's website, but if that's not an option, grab a yardstick and tape measure and follow these steps:

  • Step 1: Lay the wheel on its side with the interior side of the mounting surface facing up. Be sure to do this on a soft surface so you don't scratch the rim. For the most accurate reading, leave the tire off.
  • Step 2: Lay a yardstick (or other flat edge) across the diameter of the wheel and measure from the ground up to the yardstick to get the width. Use millimeters to make the next step easier and more accurate.
  • Step 3: Find the wheel's centerline by dividing the width by two. Record this number.
  • Step 4: Leaving the yardstick in place, measure the distance from the face of the mounting hub to the edge of the yardstick in millimeters.
  • Step 5: Subtract the centerline (step 3) from the measurement in step 4 to get the offset.

What the Offset Calculation Means

Once you've got a number calculated from the measurements above, here's what it means for your offset:

  • If you have a positive number (e.g., 146 mm - 134 mm = 12 mm), you've got a positive offset. 
  • If you have a negative number (e.g., 146 mm - 164 mm = -18 mm), you've got a negative offset. 
  • If the number is the same (e.g., 146 mm - 146 mm = 0 mm), you've got a zero or neutral offset.

What Is Wheel Backspacing?

Wheel backspacing is the distance between the back of the mounting pad and the wheel's back edge or lip. Wheel backspacing determines the amount of space your wheel needs to be able to clear without interfering with the suspension components or rubbing against the wheel well itself.

To accommodate a more negative offset, you'll likely need a wider wheel and tire combination. But be careful—more backspacing can lead to less articulation. As more of the wheel sits within the wheel well, there's potentially less range of motion available for the front wheels to turn inside the well without touching anything.

How Backspacing Is Measured

Measuring backspacing is a pretty similar process to measuring offset. To start, get a tape measure and a rigid, flat surface like a yardstick, and then follow these steps:

  • Step 1: Lay your rim facedown on a soft surface with the inside face of the mounting surface facing up.
  • Step 2: Lay a yardstick across the rim, making sure it extends past the lip on both sides.
  • Step 3: Measure from the mounting surface up to the edge of the yardstick in inches.

Backspacing vs. Offset

The difference between backspacing and offset on wheels is that backspacing measures the distance between a wheel's mounting surface and the back edge of the rim, while offset measures the distance between the mounting surface and the rim's centerline. That means the more negative the offset, the greater the backspacing; the more positive the offset, the lower the backspacing.

As far as their measurements go, backspacing is typically measured in inches, while offset is usually measured in millimeters. Backspacing is also always a positive number, while offset can be either negative or positive, depending on its relation to the centerline.

Wheel Offset Chart

Want to save yourself the trouble of measuring your wheel's offset or backspacing? If you've got the width and either the offset or the backspacing, just plug the numbers into the chart below to get the missing measurement.

A detailed wheel offset and backspacing chart.

How Does Offset Work on Wheels?

Offset works by allowing the wheel to be mounted a certain distance either away from or closer to the frame of a vehicle. Contrary to what you might expect, a more positive offset rim will sit deeper into the wheel well, while a more negative offset one will have more poke and a more aggressive stance.

But, you can't just throw any wheel with any offset onto your rig and expect it to be OK. The wrong offset can hurt longevity, safety, and handling.

What Happens If There's Too Much Positive Offset?

Too much positive offset can cause a handful of problems. It should be pretty obvious if you've taken this too far since the wheel will make contact with either the suspension components or the wheel well when you turn. Signs of an over-positive offset include:

  • Reduced articulation
  • Brake and/or suspension interference
  • Wheel and/or tire rubbing

What Happens If There's Too Much Negative Offset?

If you try to get a bit too aggressive with your stance, you could end up with too much negative offset. Some of these problems can be solved by adding fender flares or trimming some of the fender flare plastic to make space for the wider turning radius. Signs of an over-negative offset include:

  • Kickback of dirt, grit, and debris
  • Added stress to suspension components
  • Potentially reduced handling

Wheel Offset Tips

Ready to go for that neutral offset or more aggressive stance? Here's a summary of key offset tips to consider when shopping for new wheels:

  • Appropriate offset maintains handling, longevity, and safety.
  • If you don't want to change the stance, try to keep offset within 5 mm for new wheels.
  • Keep the same load capacity.
  • More negative offsets may require wider wheels and tires.
  • When in doubt, see a tire professional to ensure safety.

With wheel offset explained in detail, hopefully you've got a better idea of how it affects your truck's wheel and tire options. More and more people are buying aftermarket products like these to mod their vehicles, so it's important to know what your options are so you can keep your ride safe while getting the look and performance you want.

FAQs

Does Wheel Offset Matter?

Wheel offset matters quite a bit if you want to change your vehicle's stance. Wheel offset affects how far a wheel sticks out beyond the fender or how far within the wheel well it sits. Having too much positive or negative offset can also affect your suspension components, worsen the handling, or lead to rubbing or damaged tires.

What Is a Normal Wheel Offset?

Stock wheel offset is usually positive for most vehicles. That means if you want a flush or aggressive stance, you'll have to look into new wheels with zero or negative offset.

How Do I Find My Wheel Offset?

You can find your wheel's offset by checking the owner's manual or by looking up the model on the manufacturer's website. To measure it yourself, first find the centerline by measuring the width of the wheel and dividing by two. Then, lay a yardstick across the diameter of the wheel and measure from the back of the mounting surface to the edge of the yardstick. Subtract the centerline measurement from this to get the offset in millimeters.

What Is the Offset of a Wheel?

The offset of a wheel is the amount of space between its mounting surface and the wheel's centerline. This tells you whether the offset is positive (meaning the wheel will sit closer to the suspension components), negative (meaning it will sit closer to or poke out beyond the fender), or zero (meaning the edge of the wheel will be flush with the fender).



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