What is a DOCX file?

A DOCX file is a document in the Office Open XML format, the default format of Microsoft Word since Word 2007. It's the most common format for editable documents: resumes, reports, contracts and school assignments are usually passed around as .docx files.

What's inside a DOCX file

A DOCX file is actually a ZIP archive. Inside are XML files describing the text, styles and layout, plus any images, in separate folders. That structure is an open standard (ECMA-376 and ISO/IEC 29500), which is why so many apps besides Word can read and write it.

DOCX vs DOC

.doc is the older binary format used by Word 97 to 2003. DOCX replaced it and is usually smaller, less prone to corruption and easier for other apps to read. Current versions of Word still open DOC files; when you save one, Word offers to convert it to DOCX.

How to open a DOCX file without Word

• Google Docs opens and edits DOCX files in the browser.
• LibreOffice Writer is a free desktop app for Windows, Mac and Linux.
• Pages on Mac, iPhone and iPad opens DOCX files.
• Our Word editor opens DOCX files in your browser, without an account or an upload.

Complex documents can look slightly different outside Word, mostly because of fonts. Why fonts change when you convert Word to PDF explains why and what to do about it.

Converting DOCX to PDF

Send a DOCX when someone needs to edit the document. When it should look exactly the same for everyone, or when it's final, send a PDF instead. Our Word to PDF converter turns DOCX files into PDFs in your browser, using metric-compatible fonts to help preserve the layout. Check the result, as page breaks can differ from Word. See DOCX vs PDF for when to send which.