Document format
What is a DOCX file?
DOCX is Microsoft Word's document format — an editable, reflowable format built for drafting and revising text.
DOCX replaced Word's older, proprietary .doc format starting with Office 2007, switching to Office Open XML — a structure of readable XML files zipped together, which is more transparent, more resistant to corruption, and typically more compact than the binary format it replaced. Because it's a reflowable format rather than a fixed layout, the same DOCX file can look subtly different across different versions of Word or competing editors depending on installed fonts and rendering engines, which is exactly the kind of inconsistency PDF was built to avoid.
How to open a DOCX file
DOCX files open readily in Microsoft Word, Google Docs, Apple Pages. For real editing rather than just viewing, reach for Microsoft Word, LibreOffice Writer (free).
Strengths & limitations
Good for
- fully editable text, styles, and formatting
- the standard format for word processing
Watch out for
- layout can shift slightly between different versions of Word or other editors
Convert DOCX files
Orbfile can convert DOCX both ways, entirely in your browser — pick a direction below:
Frequently asked questions
What does a DOCX file contain?+
DOCX is Microsoft Word's document format — an editable, reflowable format built for drafting and revising text.
Can I convert DOCX for free?+
Yes — Orbfile's document converter handles DOCX for free, with no file limit, watermark, or account, and it runs entirely in your browser.
Is converting a DOCX file safe and private?+
Yes. Orbfile processes DOCX files locally on your device using WebAssembly — nothing is uploaded to a server, so there's nothing to leak or store.
Who created the DOCX format?+
DOCX was developed by Microsoft, first released around 2007.
Browse the full file format guide.