Wing loading is usually listed as Ounces/Sq Ft.

Example

So on a UCD3D the wing area is 1072 sq in.

To convert that to square feet you divide it by 12 TWICE to get 7.44 sq ft.

Advertised weight is 7 lbs to 7lbs 6oz. wishful thinking.

More like 8 to 9 lbs.

But lets assume the factory weight for now.

convert pounds to ounces by multiplying 7 by 16 (16 oz per pound)

That would give you a range of 112 to 118 ounces

112/7.44 = 15.05 oz/sq ft
118/7.44 = 15.86 oz/sq ft

Realisticly 8-9 lbs it comes in at 17.2 to 19.35 oz/sq ft.

So like golf, the lower the number the better (slower it will fly before stalling)