Documents

What is a DOCX file?

Updated Jul 2026

Definition

DOCX is the file format Microsoft Word uses to save documents, from letters and resumes to reports and contracts. It's a lossless format, so text, formatting, images, and layout stay exactly as you left them. The catch is that it can carry hidden extras like author names, edit history, and comments that travel along with the file.

DOCXMicrosoft Word document

Extension: .docx
Type: Documents
Typically: Word documents
Metadata: Carries EXIF

Why DOCX exists

Microsoft introduced DOCX with Word 2007, replacing the older DOC format. Under the hood, a DOCX file is actually a zipped folder of XML files describing the text, styles, images, and layout, which is why it opens faster and survives corruption better than the old binary DOC format.

In practice, a DOCX just holds a Word document: paragraphs, fonts, headings, tables, tracked changes, comments, images, anything you'd build in a word processor. Because it's structured XML rather than a locked-down format, other apps can read and write it too, which is part of why it became the default way people exchange documents.

People run into DOCX constantly: a resume needs to go out as a Word file, a form gets emailed for someone to fill in, or a shared draft needs to move between people using different word processors. It also comes up when someone wants a PDF instead, either to lock the layout down or to stop the recipient from editing it.

The trade-offs

Strengths

Keeps text, formatting, and images exactly as saved (lossless)
Editable, so recipients can change or fill in the document
Widely supported across word processors, not just one program
Handles long, complex documents with styles and tables well

Watch-outs

Can carry hidden metadata like author name and edit history
Formatting can shift slightly when opened in a different program
Not ideal for sharing a final version you don't want edited
Larger and less portable for quick viewing than a PDF

A note on privacy

A DOCX file can quietly carry metadata such as the author's name, the computer it was created on, past edits, and comments left during review. If you convert it through an online tool, that document and everything embedded in it gets uploaded to someone else's server first. Converting on your own computer means the file, and whatever history is baked into it, never leaves your machine.

Convert a DOCX file

Questions

How do I open a DOCX file?

Word opens it natively on Mac and Windows, and most other word processors can open it too. If you don't have one installed, converting it to PDF lets you view it in any browser.

Is DOCX better than PDF?

For editing, yes: DOCX keeps the document changeable. For sharing a final version, PDF is usually better since it locks the layout and looks the same on every device.

Why does my document save as DOCX by default?

It's Word's standard save format since 2007, built to be more reliable and compact than the older DOC format. Most word processors default to it for the same compatibility reasons.

Can I convert DOCX without uploading it?

Yes. A desktop app like Morphjet converts DOCX on your own computer, so the document and any metadata inside it never travel over the internet.

Morphjet opens and converts DOCX and 1,800+ other formats, all on your own computer. Launching this July.