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DOC to DOCX Converter

Convert DOC to DOCX online for free. Use this converter when you need better editability, fixed-layout sharing, office compatibility, or a document format that fits your workflow better.

Converting DOC to DOCX re-encodes the document into the DOCX container. Text, headings, tables, images, and basic formatting are preserved; advanced features (macros, comments, tracked changes) may not carry across all format pairs.

Drop DOC files here
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Files deleted within 24 hours TLS-encrypted upload No sign-up required Batch convert supported

Max file size 50MB. Sign up for more.

What to expect when converting DOC to DOCX

Typical file-size change
20–50% smaller
Example

A 500 KB legacy DOC typically becomes 250 – 400 KB as DOCX.

Quality: None for visual content. Some legacy features (specific macros, old WordArt) may not survive — DOCX is a stricter format.

Best for: modernizing legacy Word documents — DOCX opens cleanly in current Word, Google Docs, LibreOffice, and iOS Pages.

Avoid when: the recipient explicitly needs the old binary DOC format (rare today).

Tip: DOC was deprecated by Microsoft in 2007. Converting to DOCX is the right move for any Word doc you still need to maintain.

Convert DOC Documents in 3 Steps

Move a document into a more shareable or editable format while keeping layout, text structure, tables, and embedded media intact where possible.

Upload the Original Document

Drag and drop your DOC file or click to browse. Supports text documents, reports, manuscripts, and files with images, tables, and formatting. Batch upload multiple files at once.

Convert the Layout

Our engine converts your DOC to DOCX while preserving text formatting, paragraph styles, images, tables, headers, footers, and page layout as faithfully as possible.

Download the Converted File

Download your converted DOCX document instantly. For batch conversions, download all files individually or as a single ZIP archive. No watermarks or quality loss.

Why Convert DOC to DOCX

Full Editing Capability

DOCX files are fully editable in Microsoft Word, Google Docs, LibreOffice, and Apple Pages. Unlike PDF, every paragraph, image, table, and style can be freely modified after conversion.

Track Changes and Comments

DOCX supports revision tracking, inline comments, and suggested edits. Collaborative document workflows in teams, legal reviews, and academic peer review all depend on these editing features.

Professional Formatting

DOCX supports styles, headers, footers, page numbers, table of contents, footnotes, endnotes, and bibliography management. Create professionally formatted documents with consistent typography.

Microsoft 365 Integration

DOCX is the native format of Microsoft Word and integrates seamlessly with SharePoint, OneDrive, Teams, and the entire Microsoft 365 suite. Real-time co-authoring works best with DOCX files.

Mail Merge Support

DOCX documents connect to data sources for mail merge operations, generating personalized letters, labels, envelopes, and certificates. Essential for mass communications and automated document generation.

DOC vs DOCX: Side-by-side

Technical comparison of the two formats — useful for deciding which to use, or for confirming what changes during conversion.

Property DOC DOCX
Full name Microsoft Word (legacy binary) Microsoft Word (Open XML)
Year introduced 1983 2007
Developer / standard body Microsoft Microsoft
MIME type application/msword application/vnd.openxmlformats-officedocument.wordprocessingml.document
File extension .doc .docx
Compression Compound File Binary Format ZIP-compressed XML
Color / data depth N/A (text) N/A (text)
Max dimensions / size 32 MB file size limit 32 MB recommended
Transparency No No
Animation No No
Standard / specification Microsoft (binary) ECMA-376 / ISO/IEC 29500
Best for Legacy Word compatibility (1997–2003 era) Modern Word documents, collaborative editing

About the DOC Format

DOC is Microsoft Word's legacy binary document format, used as the default from Word 97 through Word 2003. Unlike the modern DOCX format which uses ZIP-compressed XML, DOC stores content in a proprietary binary structure called OLE2 (Object Linking and Embedding). While largely replaced by DOCX, millions of DOC files still exist in business archives, legal repositories, and government records.

DOC files support rich text formatting, embedded images, tables, headers, footers, and macros. However, they are larger than equivalent DOCX files, more prone to corruption, and harder for third-party software to parse correctly. Modern versions of Word, Google Docs, and LibreOffice can still open DOC files, but converting to DOCX or PDF is recommended for long-term compatibility and smaller file sizes.

DOC to DOCX FAQ

Quick answers about compatibility, quality, metadata handling, and the most common reasons to convert DOC files to DOCX.

How do I convert DOC to DOCX online?

Upload your DOC document, choose DOCX as the output format, and download the converted file when the job finishes.

Why would I convert DOC to DOCX?

People usually convert DOC to DOCX to improve editability, preserve a fixed layout, match office software requirements, or fit a sharing and printing workflow. DOCX is usually the better target when you need a Word file you can edit.

Will converting DOC to DOCX keep formatting intact?

Standard text, headings, and common layouts usually convert well, but complex formatting, custom fonts, and unusual layouts may need review after conversion.

How will file size change when converting DOC to DOCX?

File size can change depending on the document structure, fonts, images, and target format.

Can I batch convert multiple DOC files to DOCX?

Yes. Batch conversion is useful for contracts, reports, office exports, and repetitive admin workflows.

Is it safe to convert DOC to DOCX online?

Yes. This converter uses temporary browser-based processing with automatic cleanup after conversion.

Why should I convert old DOC files to DOCX?

DOC was deprecated by Microsoft in 2007. DOCX is smaller (20–50% reduction), opens reliably in current Word / Google Docs / LibreOffice / iOS Pages, and supports modern features like accessibility tags. Old DOC files may break in newer Word versions.

Will I lose any content converting DOC to DOCX?

Typical document content (text, formatting, tables, embedded images) carries cleanly. Legacy features that may not survive: very old WordArt, certain macros designed for Word 2003, and some specialized OLE objects.

Document Conversion Guides for DOC to DOCX Converter

Read guides about PDF, Word, and editable document workflows connected to DOC to DOCX Converter.