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File type: Microsoft Word Open XML Document


The usage of the DOCX file extension is commonly associated with the Open XML document format generated by the Microsoft Office Word 2007 application.
This software is a component of the Microsoft Office 12 and is founded on the Open XML standards coupled with a ZIP compression algorithm to reduce the size of the file. Since this new document standard is distinctly different from the DOC file format in previous versions of the application, Microsoft released an Office Compatibility Pack which is basically a file format converter that would allow previous releases of the Microsoft Office Productivity Suite to access the DOCX file formats. The Open XML standard used by the new document file version of Office Word was intended to represent word processing files, presentations, charts, and spreadsheets. The Office Open XML file format specification became an open and free standard in 2006. Microsoft implemented its version as a successor to the earlier binaries of its applications and to the Office 2003 XML format files.

Detailed information 

Category: Text Files
File format: Proprietary
Open with Windows: Microsoft Word 2007, Word 2000, XP, and 2003 with the Compatibility Pack installed, Panergy docXConverter, OxygenOffice Professional, with Odf-Converter, NativeWinds Docx2Rtf
Open with Linux: OxygenOffice Professional, with Odf-Converter
Beginning with the Microsoft Office 2007, the ECMA-376 (OOXML format) became the default format for all Office Word document files. Microsoft Office 14 would be the first commercially available productivity suite to employ the ISO/IEC IS 29500 specification compliant edition of the Office Open XML.
Before the market launch of the Microsoft Office 2007 suite, the central applications incorporated in the productivity package included Word, PowerPoint, and Excel.
These applications, by default, saved data in binary files which lacked interoperability functionality making them difficult to access from other applications in the same category.
The problem arose from the absence of a publicly available royalty-free data which would allow access to the specifications of file formats.
The initial release of the XML-based file format was made by Microsoft in 2000 via the Office Excel spreadsheet application. It followed with the Word XML format in 2002 and together with Excel was integrated into the Microsoft Office 2003 commercial release.
The DOCX file extension is seen as the new standard that would be followed by Microsoft Word for all its future releases as part of the standardization process for word processing documents in the IT industry.