Wheel Poke and Inset Calculator

Before interpreting the answer

Calculate approximate wheel extension outward and inward from the hub face — the equation describes geometry or tire behavior for one defined setup.

Tire section width can extend beyond the wheel — that condition defines when outer position from hub is comparable with another result.

How to document the calculation

Measure the installed component and the vehicle reference points rather than relying only on a catalog dimension — this workflow must also account for the fact that tire section width can extend beyond the wheel.

• Record Overall wheel width as measured total wheel width — measure from the stated reference points and note whether the vehicle or component is loaded.
• Record Wheel offset as positive offset moves the wheel inward — measure from the stated reference points and note whether the vehicle or component is loaded.
• Record Reference plane position as optional body or hub reference adjustment — use a measurement or specification from the exact component and operating condition being evaluated.
• Repeat the check only after accounting for this condition: tire section width can extend beyond the wheel.

How the quantities interact

Overall wheel width. Measured total wheel width — for this measurement, measure from the stated reference points and note whether the vehicle or component is loaded.

Document Wheel offset as positive offset moves the wheel inward — this means you should measure from the stated reference points and note whether the vehicle or component is loaded.

The Reference plane position entry represents optional body or hub reference adjustment — before calculating, use a measurement or specification from the exact component and operating condition being evaluated.

In “outer position = half width − offset. inner position = half width + offset,” the calculation does not infer a missing vehicle measurement.

No term beyond overall wheel width, wheel offset, and reference plane position is introduced in “outer position = half width − offset. inner position = half width + offset.”

What requires independent verification

Suspension travel, steering angle, tire growth, body tolerances, and alignment can reveal interference that a static dimension misses — for overall wheel width, the page specifically expects measured total wheel width.

An example with recorded units

To trace the arithmetic, start with Overall wheel width = 9.5 in, Wheel offset = 35 mm, and Reference plane position = 0 in.

After applying the formula, the displayed results are Outer position from hub = 3.37 in, Inner position from hub = 6.13 in, and Offset in inches = 1.378 in.

The current equation stops before the step needed to estimate contact area using load, pressure, and an empirical shape factor, which is handled by the Tire Contact Patch.

Putting the number in context

Outer position from hub answers “Calculate approximate wheel extension outward and inward from the hub face.” The additional displays, Inner position from hub and Offset in inches, are a different view of the same entered measurements.

Use measured clearances and account for suspension movement and steering — when that condition changes, compare separate calculator runs instead of blending the inputs.

Because tire section width can extend beyond the wheel, a disagreement between outer position from hub and an outside reference should trigger a review of overall wheel width and reference plane position.

For a second calculation that will estimate total capacity for tires used in dual positions, use the Dual-Tire Load Capacity.

Clarifying the calculation