Additional Information A cuboid is the shape which is most commonly seen as a box for packaging things in. Some fancy packaging (particularly for sweets) is done in shapes other than cuboids, but not so often. If you buy a pair of shoes and ask to have them in a box, it is almost certain that the box will be a cuboid. Formally, we would say that a cuboid is a 3dimensional shape (or polyhedron) having 6 faces, each of which is a rectangle. Remembering that a rectangle can be a square as well as an oblong, then we have a special case:if all faces of a cuboid are squares  it is a cube.The size of a cuboid is defined by 3 edgelengths which are usually all different, but do not have to be. (Again, if they are all the same it is a cube.) Though the edges are given numbers on screen (edge 1 etc.), this has NO physical meaning, so values of 3, 5, 8 produce the same results as 8, 5, 3 etc. The volume is found by multiplying these 3 edgelengths together. The surface area is the combined areas of all 6 faces. 

Space diagonal Each of the 6 rectangular faces contains 2 diagonals, and these are described as face diagonals Inside the cuboid
there are 4 more diagonals. These connect any two opposite vertices which do
not belong to the same face. They are called the space diagonals. All 4 are equal in length.
Cautions The message that 'No solution was found' means only that. So, if a solution is possible then it was outside the limits set within this calculator. Also, in some cases, more than one solution might be possible, but only one (the first one found) is given here. If a value of 0 (zero) is given, it means that a solution is possible but is too small to be of any real use. 