What is DOC?
Complete guide to the DOC file format
What is it?
DOC is the binary file format used by Microsoft Word from version 1.0 in 1983 through Word 2003. It stores word processing documents including text, formatting, images, tables, embedded objects, and revision history in a proprietary binary structure. DOC files use Microsoft's Compound Document File Format (also called OLE Structured Storage), which was designed for Windows and is closely tied to the Windows COM/OLE infrastructure.
In 2007 Microsoft replaced DOC as the default format with DOCX, which uses the open XML-based Office Open XML standard. Despite being superseded, DOC files remain in use because they are still fully supported by all versions of Microsoft Word, LibreOffice, and Google Docs. Organizations with documents created before 2007 often retain DOC files rather than converting them. DOC files can also contain macros, which has made the format a common vector for malware distribution.
Technical Specifications
Pros & Cons
Advantages
Supported by virtually all word processors including Word, LibreOffice, WPS Office, and Google Docs.
Necessary for opening and editing documents created before 2007 without format conversion.
Preserves formatting, macros, embedded objects, and revision marks from older Word versions.
Documents created in older Word versions open with their original formatting intact.
Disadvantages
The binary structure is difficult to parse, repair, or read without Microsoft Office or compatible software.
DOC files can contain VBA macros that have historically been used to distribute malware.
Binary DOC files are often larger than equivalent DOCX files which use XML with ZIP compression.
Lacks support for modern Word features added after 2007 and is no longer the format Word saves in by default.
When to Use It
Here are the most common situations where DOC is the right choice:
Legacy Document Compatibility
Use DOC when you need to share documents with organizations or software that require Word 97-2003 compatibility.
Older Client Requirements
Some government and institutional systems still require .doc format for document submissions.
Pre-2007 Archive Access
Open and work with archived DOC documents from pre-2007 word processing systems.
Convert to DOCX
Migrate DOC files to DOCX format using Word or LibreOffice to benefit from the modern XML-based format.
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Start Converting NowFrequently Asked Questions
What is the difference between DOC and DOCX?
DOC is the older binary format used before Word 2007. DOCX is the XML-based Office Open XML format introduced in Word 2007. DOCX is smaller, more transparent, and the current default. Word can open and save both formats.
Can LibreOffice open DOC files?
Yes. LibreOffice Writer fully supports DOC files and can open, edit, and save them without conversion.
Are DOC files safe?
DOC files can contain macros that execute code. Only open DOC files from trusted sources and keep macros disabled unless you specifically need them from a trusted document.
How do I convert DOC to PDF?
Use our free converter, Microsoft Word's "Export to PDF" option, or LibreOffice to convert DOC files to PDF.
Can Google Docs open DOC files?
Yes. Google Docs can open, display, and edit DOC files. However, some complex formatting with macros or advanced layout may not be fully preserved.