XMCDZ files are XML based worksheet files that have been created with the use of MathCAD software. MathCAD is a program that is commonly used in the creation of engineering and scientific calculations. The XMCDZ file may include both mathematical and textual elements. The XMCDZ file is very similar to a .XMCD file, but the .XMCDZ file is saved in a compressed format, while the XMCD file is entirely uncompressed.