Word Document — Microsoft Word document based on Office Open XML.
Quick facts
What is .docx
A .docx file is a Word Document — Microsoft Word document based on Office Open XML.
In the mime-db registry it maps to application/vnd.openxmlformats-officedocument.wordprocessingml.document, and it is marked as non-compressible. When serving .docx over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to application/vnd.openxmlformats-officedocument.wordprocessingml.document — and is delivered over HTTP via the Content-Type header.
How to open .docx files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
Common software that reads/writes .docx:
Relation chain
Related extensions
Related MIME types
Common uses
How to edit .docx files
How to create .docx files
Frequently asked questions
Common options include Microsoft Word, LibreOffice, Google Docs. You can also open many of these files with built-in viewers or a browser.
Create a new file in any text editor or the app that owns the format and save it with the .docx extension.
application/vnd.openxmlformats-officedocument.wordprocessingml.document is the media type identifier used for .docx files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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