How to Measure UTV Wheel Offset and Backspacing

UTV wheel offset is the distance, in millimeters, between the wheel's centerline and its hub-mounting surface. It is not the distance between the front and rear axles. To estimate an unmarked wheel's offset, measure its backspacing and overall width, then calculate the difference from the centerline. Before buying, confirm that result against the wheel manufacturer's specification for the exact part number.

This guide focuses on measuring a wheel you already have. For tire sizes, bolt patterns and beadlock choices, start with our UTV wheel and tire size guide.

Offset, backspacing and width: three different measurements

• Offset: the signed distance from the wheel centerline to the mounting plane, usually listed in millimeters.
• Backspacing: the distance from the hub-mounting pad to the inboard rim edge, commonly listed in inches.
• Nominal wheel width: the advertised width between the tire bead seats. It is different from the overall width across the outside rim lips used in the calculation below.

Positive offset places the mounting plane toward the wheel's outward-facing side; zero offset puts it at the centerline; negative offset places it toward the vehicle-facing side. When comparing equal-width wheels on the same hub, a lower offset moves the wheel outward. Neither zero nor negative offset is automatically the right choice for a UTV.

Start with the wheel's part number

Before reaching for a ruler, look for markings and record the wheel's brand, part number, size and any offset marking. Photograph the markings and the mounting side. Front and rear wheels may differ, so record them separately instead of assuming one measurement describes the whole set.

If the listing, stamped marking and measurement disagree, stop the comparison there. Ask the manufacturer or seller to identify the exact wheel. A calculation can help spot a mismatch; it cannot establish vehicle compatibility.

How to measure backspacing and calculate offset

Use a straightedge, an accurate ruler or depth gauge, and a protected flat work surface. A bare wheel gives the clearest access. If a tire prevents the straightedge from contacting the rim lips, do not use the tire sidewall as the reference. Have a tire shop help with removal when necessary. Follow your vehicle's service instructions for wheel removal and installation.

1. Identify the mounting pad. Find the machined surface that contacts the vehicle's hub. Do not measure to a center cap, spoke or decorative recess.
2. Measure backspacing. Place the wheel face down on a protected surface. Rest the straightedge across the inboard rim lips. Measure perpendicularly from the mounting pad to the underside of the straightedge, at the plane where it touches the lips.
3. Measure overall width. Record the outside-lip-to-outside-lip width of the wheel. Do not substitute the advertised bead-seat width.
4. Calculate the centerline. Divide the overall width by two.
5. Calculate offset. Subtract that half-width from backspacing. If measured in inches, multiply the result by 25.4 to express offset in millimeters.

Estimated offset (mm) = [backspacing (in) − overall width (in) ÷ 2] × 25.4

The lip-based method is a practical estimate. Use the manufacturer's stated offset when flange geometry or measurement access makes the centerline uncertain. Overall width is often roughly one inch greater than nominal width, but measuring the actual wheel is preferable to treating that allowance as exact.

Worked example: keep the units consistent

Suppose a wheel measures 8 inches overall and has 5 inches of backspacing. Half the overall width is 4 inches. Subtracting 4 from 5 gives 1 inch; multiplying by 25.4 gives an estimated +25.4 mm offset. These are hypothetical measurements, not a specification for a wheel sold by RAD.

A common mistake is using a 7-inch advertised width in that same calculation. That would produce +38.1 mm—an error of 12.7 mm caused by mixing bead-seat width with outside-lip backspacing.

What a change in offset means

For two wheels of equal width, changing from +30 mm to +15 mm moves each wheel's centerline outward by 15 mm. If both sides of the same axle change equally, wheel-center track increases by 30 mm. This arithmetic does not predict the vehicle's overall tire width, fender coverage or rubbing clearance.

If wheel width also changes, compare both the inner and outer positions. Do not choose from offset alone. Tire dimensions, brake clearance and the vehicle's suspension and steering movement still need checking for the exact combination.

Reading 4+3, 5+2 and other UTV wheel labels

When a listing uses a split-inch label, ask for the exact part number's offset in millimeters and backspacing. Do not treat a rounded shorthand label as a precision measurement or assume two brands use it identically. Save the specification sheet with your shopping notes so you can compare the same units across options.

A fitment worksheet before ordering

For a KRX 1000, Maverick R, Honda Pioneer 700 or another UTV, build your shortlist around the exact machine—not the model family alone:

• Vehicle: year, model, trim, seating configuration and suspension or hub modifications.
• Existing setup: front and rear wheel part numbers, diameter, width, offset and tire sizes.
• Candidate wheel: exact SKU, bolt pattern, center-bore requirements, load rating and manufacturer application notes.
• Hardware: correct stud thread, lug-seat type and installation requirements. See our UTV wheel stud and hardware fitment guide.
• Clearance: brakes, steering and suspension throughout their required operating movement, plus bodywork and tire clearance.
• Package contents: quantities, tire sizes, hardware, mounting services and whether the front and rear specifications differ.

Use that worksheet to compare UTV wheels or wheel and tire packages. If an essential specification is missing, get it confirmed before ordering. A matching bolt pattern or offset alone is not a fitment guarantee.

Measurement references

The definitions and measurement method were checked against American Racing's offset and backspacing explanation, Circle Racing's wheel measurements and Speedway Motors' WheelWise instructions (pages 1 and 8). These references explain measurement principles; their vehicle-specific examples do not establish UTV fitment.