All formats

What is a DOCX file?

DOCX is the default Word format since Office 2007 and a published standard as ECMA-376. Under the hood it is a ZIP archive of XML files, which is why it is far more recoverable than the old binary DOC and why other applications can read it reasonably well.

At a glance

Full name
Office Open XML Document
Extensions
.docx
Type
Document
Introduced
2007
Created by
Microsoft; ECMA-376 / ISO 29500
Compression
Lossless
MIME type
application/vnd.openxmlformats-officedocument.wordprocessingml.document

Strengths

  • Editable, with tracked changes, comments and styles
  • Open standard, so many applications can read and write it
  • Content reflows to fit the screen or page

Limitations

  • Layout can shift between applications and platforms
  • Not suitable as a final, fixed-layout deliverable

When to use DOCX

Use it when

A document is still being written, reviewed or collaborated on.

Avoid it when

Sending a final deliverable where layout must be guaranteed. Export to PDF.

Convert DOCX files

Every tool below runs in your browser unless it is labelled otherwise, so the file stays on your device.

DOCX conversions

Each page states what the target format cannot carry before you run it.

DOCX compared

Related document formats

Last updated 2026-08-03