Cross-Weight Percentage Calculator

What this calculation answers

Calculate diagonal cross-weight percentage from four scale readings — a calculated performance value does not establish a safe operating limit.

Vehicle condition, fuel, driver ballast, tire pressure, and pad level must remain consistent — that condition defines when cross-weight percentage is comparable with another result.

Equation and unit relationship

In “cross weight = (right front + left rear) ÷ total weight × 100,” the relationship answers the question stated above without adding an unstated correction factor.

No term beyond left-front weight, right-front weight, left-rear weight, and right-rear weight is introduced in “cross weight = (right front + left rear) ÷ total weight × 100.”

Measurements and source records

Left-front weight is defined here as left-front scale reading — keeping that definition intact requires you to use the same loaded condition for every weight and retain the scale ticket or rating source.

For Right-front weight, use the quantity described as right-front scale reading — in the vehicle record, use the same loaded condition for every weight and retain the scale ticket or rating source.

Left-rear weight: Left-rear scale reading — a compatible entry should use the same loaded condition for every weight and retain the scale ticket or rating source.

The Right-rear weight entry represents right-rear scale reading — before calculating, use the same loaded condition for every weight and retain the scale ticket or rating source.

Build another useful comparison to estimate four-stroke engine airflow for carburetor sizing with the Carburetor CFM.

Worked values from the loaded form

A worked pass through the equation uses Left-front weight = 910 lb, Right-front weight = 870 lb, Left-rear weight = 830 lb, and Right-rear weight = 890 lb.

The completed example reports Cross-weight percentage = 48.57% and Total vehicle weight = 3,500 lb.

When the vehicle decision also requires you to apply an entered air-density relationship to a measured power value, calculate it independently with the Air Density Correction.

Reading the output

Cross-weight percentage answers “Calculate diagonal cross-weight percentage from four scale readings.” The additional display, Total vehicle weight, is a different view of the same entered measurements.

Cross weight is one setup metric rather than a universal target — when that condition changes, compare separate calculator runs instead of blending the inputs.

Because vehicle condition, fuel, driver ballast, tire pressure, and pad level must remain consistent, a disagreement between cross-weight percentage and an outside reference should trigger a review of left-front weight and right-rear weight.

Traction, grade, wind, temperature, driver input, and control-system intervention remain outside this simplified model — for left-rear weight, the page specifically expects left-rear scale reading.

Questions specific to this calculation