DOCX is the modern Word format — a ZIP archive of XML files following the Office Open XML (OOXML) standard introduced with Microsoft Office 2007. DOC is the legacy binary format based on OLE2 compound document structure that Word used from 1997 to 2003. Converting DOCX to DOC downgrades a modern document to the older format for compatibility with systems that have not been updated in nearly two decades.

The conversion flattens DOCX's XML-based structure — where paragraphs, styles, and metadata are stored as separate, well-defined XML elements — into the binary stream format of DOC. This reverse migration preserves standard formatting while sacrificing DOCX-specific features like content controls, structured document tags, and equation objects that have no DOC equivalent.

Legacy systems in government, legal, healthcare, and manufacturing often require DOC format because their document management software was deployed before 2007 and never upgraded. Court filing systems, ERP document modules, and industrial control interfaces built around Word 97-2003 frequently reject DOCX files. Converting to DOC ensures your documents are accepted by these older systems.

Some older versions of Microsoft Word (2003 and earlier) cannot open DOCX files without installing the Microsoft Office Compatibility Pack, which is itself no longer supported. If your recipients are running Word 2003 or earlier — common in organizations with strict IT change control policies — DOC is the only format they can open natively without additional software.

LibreOffice imports the DOCX file by parsing its ZIP structure, reading word/document.xml for body content, word/styles.xml for formatting definitions, and extracting media from the word/media/ directory. The document model is then serialized into the DOC binary format using the OLE2 compound file writer. OOXML paragraph properties (<w:pPr>) are mapped to Word 97 SPRMs (Single Property Modifiers), character formatting (<w:rPr>) becomes character-level SPRMs, and table structures (<w:tbl>) are written as binary table definitions. Features without DOC equivalents — content controls, SmartArt, MathML equations, theme colors — are either degraded to simpler representations or omitted.

Content controls, SmartArt graphics, MathML equations, theme colors, and some OpenType typography features. Standard formatting — fonts, styles, tables, images, headers, footers — is preserved.

Usually larger. DOCX uses ZIP compression, while DOC is an uncompressed binary. Text-heavy documents may grow 50-100% when saved as DOC.

Yes, but features that were lost in the DOCX-to-DOC conversion cannot be recovered. Always keep the original DOCX as your primary copy.

Most comments and tracked changes survive the conversion. However, the DOC format tracks changes differently, so some complex revision histories may simplify.

Only if your recipient or system requires it. For all other cases, DOCX is the better format — smaller, more compatible with modern tools, and more feature-rich.

Device	DOCX	DOC
Windows PC	Partial	Partial
macOS	Partial	Partial
iPhone/iPad	Partial	Partial
Android	Partial	Partial
Linux	Partial	Partial
Web Browser	No	No

Ominaisuus	DOCX	DOC
Koko nimi	Microsoft Word Document	Microsoft Word 97-2003
Tiedostopääte	.docx	.doc
Paras käyttökohde	Editable	Legacy support

Convert DOCX to DOC — Free Online Converter

Tietoa muunnoksesta DOCX–DOC

Miksi muuntaa DOCX muotoon DOC?

Yleisiä käyttötapauksia

Näin se toimii

Laatu ja suorituskyky

Laiteyhteensopivuus

Vinkkejä parhaisiin tuloksiin

Aiheeseen liittyvät muunnokset

Usein kysytyt kysymykset

Aiheeseen liittyvät muunnokset ja työkalut

Käänteinen muunnos

Muunna DOCX myös muotoon

Muunna myös muotoon DOC

Aiheeseen liittyvät työkalut

Tutustu lisää

Muunnosohjeet

Muunna DOCX muihin muotoihin

Muunna muita muotoja muotoon DOC

DOCX vs DOC