Wheel offset is the distance, in millimeters, from the wheel's mounting surface to its centerline. Positive offset tucks the wheel in toward the truck. Negative offset pushes it out, giving that wide "poke" stance. Backspacing measures the same thing differently: inches from the mounting surface to the back lip.
We check bolt pattern, offset, backspacing, load rating and brake clearance on your vehicle before any wheel is mounted, at both our Tyler and Longview shops.
What is wheel offset?
Wheel offset is how far the wheel's mounting surface sits from the center of the wheel, measured in millimeters. Discount Tire defines it as "the distance from the wheel's mounting surface to its centerline (measured in millimeters)." It's usually stamped on the wheel as "ET" or a number like +18 or -25.
Offset decides where the wheel sits in the fender. Get it right and the truck looks planted. Get it wrong and the tire either hides inside the wheel well like it's shy, or sticks out and rubs everything it touches, including your patience.
Positive vs negative offset
Positive offset puts the mounting face toward the outside of the wheel, so the wheel sits further in under the fender. Negative offset puts the mounting face toward the inside, so the wheel sits further out. Zero means the face is dead center.
Discount Tire sums up the trade: "More positive offset = more backspace (tucks in toward the vehicle). More negative offset = less backspace (pushes outward)." Most factory wheels run positive offset. Most of the aggressive truck wheels that make people turn around in the H-E-B parking lot run negative.
- Positive offset: factory look, tucked, best clearance from the fender lip
- Zero offset: a middle ground on many trucks
- Negative offset: wide stance and deep dish, more chance of rubbing at full lock
Offset vs backspacing
Offset and backspacing describe the same wheel position in two ways. Offset is millimeters from the mounting face to the centerline. Backspacing is "the distance from the mounting surface to the back lip of the wheel (measured in inches)." Backspacing is the number that tells you if the wheel will clear the suspension.
You can convert between them with a common shop formula: backspacing in inches is about half the wheel width plus half an inch, plus the offset converted to inches. It's an approximation, because real lip widths vary, but it's close enough to sort good options from bad ones before you measure for real.
For a 20x10 wheel at -25 offset: half of 10 plus half an inch is 5.5 inches, and -25mm is about -1 inch. So the backspacing is about 4.5 inches.
Picked a wheel but not sure of the offset? We check it on your actual truck before anything gets mounted. See custom wheels in Tyler and Longview.
Wheel offset chart
A wheel offset chart turns offset into backspacing so you can compare wheels. The table below uses the formula above on common truck sizes. Treat it as a starting point: the only real test is your truck, your tire and your suspension.
| Wheel size | Offset | Approx. backspacing | Stance |
|---|---|---|---|
| 20x9 | +18 mm | 5.7 in | Close to factory, tucked |
| 20x9 | +1 mm | 5.0 in | Slightly out |
| 20x10 | -18 mm | 4.8 in | Mild poke |
| 20x10 | -25 mm | 4.5 in | Noticeable poke |
| 22x12 | -44 mm | 4.8 in | Aggressive, wide |
| 24x14 | -76 mm | 4.5 in | Very aggressive |
Getting offset right on real trucks
The wrong offset usually shows up as rubbing at full turn, a tire hitting the upper control arm, or a wheel that looks lost inside the fender. On lifted trucks, big negative offset and wide tires often need trimming or a taller lift to clear.
That's why we check fitment on your truck, not off a chart. td turner drove to our Tyler shop from about an hour and a half away and wrote that Ralph "advised me on which offset wheels would give me the look I was after. He also helped me with getting the exact tires I wanted and the biggest ones that would work without rubbing or trimming."
Offset questions
Does wheel offset affect handling?
What offset is best for a lifted truck?
Can wheel spacers change offset?
Where is the offset stamped on a wheel?
Want the stance without the rub? We check bolt pattern, offset, backspacing, load rating and brake clearance on your truck before anything gets mounted. See custom wheels in Tyler and Longview, or call Tyler at (903) 500-8557 or Longview at (903) 500-9626.