.docx · application/vnd.openxmlformats-officedocument.wordprocessingml.document
What is a .docx file?
Word Document
About the format
A .docx file is a Microsoft Word document in the Office Open XML format used since Office 2007 — technically a ZIP archive full of XML parts (rename one to .zip and look inside; the text lives in word/document.xml). That structure is why .docx files are smaller and less corruption-prone than the old binary .doc, and why many tools besides Word can read and write them: LibreOffice, Google Docs, and Word's free web version all handle .docx well, with only complex layouts drifting. The security story is specifically about MACROS: a plain .docx CANNOT contain macros — macro-enabled documents use the .docm extension, and a 'document' arriving as .doc or .docm demanding you 'Enable Content' is the classic malware lure. Microsoft now blocks macros from internet-sourced files by default, which has pushed attackers elsewhere, but the instinct remains sound: never enable content on a document you weren't expecting. For just reading a suspicious document, Word's Protected View or the web viewer keeps it sandboxed.
How to open a .docx file
Windows
- Microsoft Word
- LibreOffice Writer (free)
- Word for the web (free)
macOS
- Word, Pages, LibreOffice
Linux
- LibreOffice Writer
Is a .docx file dangerous?
Plain .docx can't run macros. Treat .doc/.docm and any 'Enable Content' prompt as the actual risk.
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