DOC to DOCX
Convert legacy .doc to modern .docx.
Click to upload or drag & drop
Select a legacy Word document (.doc)
How to use the DOC to DOCX
- 1Add the legacy .doc file
Choose the old Word document from your computer, or drop it onto the panel above.
- 2Start the upgrade
Press Convert to DOCX. LibreOffice opens the binary document and rewrites its content as Office Open XML.
- 3Save the modern file
The rebuilt .docx arrives as a download the moment the engine finishes.
Examples
| Input | Output |
|---|---|
Word 97-2003 binary .doc | OOXML .docx (a ZIP of XML) |
Embedded VBA macro project | Removed — .docx cannot hold one |
Text-heavy 4 MB report | Often 1-2 MB after ZIP compression |
Tracked changes and comments | Carried across as Word revisions |
Password-protected .doc | Refused — unlock it in Word first |
Convert DOC to DOCX
A file ending in .doc and a file ending in .docx share a name and almost nothing else. The older one is a binary OLE compound file — effectively a miniature filesystem sealed inside a single file, holding named streams with names like WordDocument, Data and 1Table, plus a File Information Block at the front that tells the reader where each fragment of text actually sits. The newer one is a ZIP archive stuffed with XML: rename a .docx to .zip, open it, and you will find word/document.xml, word/styles.xml and a media folder holding the pictures. This tool reads the first and writes the second, using LibreOffice's Word filters.
What the upgrade actually buys you
- A documented format.Office Open XML is published as ECMA-376 and ISO/IEC 29500, so search indexers, archive systems and server-side pipelines can read your file without reverse-engineering a 1990s binary layout.
- Smaller files. XML compresses hard, and the ZIP wrapper does that for free.
- Better odds after corruption. If one entry in a ZIP is damaged, the rest can often still be extracted by hand. A compound file with a broken header is usually a total loss, because nothing else in it can be located.
- Fewer rejections. Upload forms that validate by extension have quietly narrowed to .docx over the past decade.
The part that is deliberately left behind
One thing genuinely does not make the journey: macro code. The old format could carry a VBA project alongside the text, and a great many 1990s templates did. Modern .docx has no compartment for that at all, which is why the macro-enabled .docm extension exists. An old macro-driven form therefore converts into an ordinary, inert document. Everything else people actually worry about — paragraph and character styles, list numbering, tables, headers and footers, footnotes, bookmarks, hyperlinks, embedded images, tracked changes and comments — comes through in normal use.
Where the new .docx goes next
Once a document is in the modern format the rest of the toolkit opens up. Send it straight to a fixed-layout copy with Word to PDF, pull out just the words with Word to Text, or hand it to a free office suite through Word to ODT. If your spreadsheets and slide decks are the same vintage, the matching upgrades are XLS to XLSX and PPT to PPTX.
Why this cannot happen inside the page
Browsers have no idea what a Word binary document is. There is no web API for compound files, and the JavaScript libraries that advertise .doc support overwhelmingly just scrape the readable characters out of one stream and discard the layout entirely. Rebuilding a real document means running the original import filters inside an office engine, so your upload is handed to a headless LibreOffice process on our machine. It gets a scratch directory created for that single request; your .doc, the finished .docx and LibreOffice's own temporary profile all live there, and the whole directory is deleted when the response ends — whether the conversion succeeded or failed.
Frequently Asked Questions
Word still opens .doc files. Why convert at all?
Because everything around Word increasingly does not. Applicant-tracking systems, e-signature services, document portals and plenty of upload forms now accept .docx only, and corporate Office installs are frequently configured to open the old binary formats read-only through Trust Center file-block policy. Converting once removes the argument.
What happens to VBA macros stored in the old document?
They are dropped, and that is not a bug in this tool. The .docx specification has no place to store a macro project — Microsoft split that off into the separate .docm format precisely so a plain .docx could be treated as inert. If the macros are the whole point of the file, keep the original .doc and open it in Word; if you were sent the file by someone you half-trust, losing them is the best part of the trip.
Will the converted file be smaller?
Usually, sometimes dramatically. The old binary container stores text and structures uncompressed, while a .docx is a ZIP archive, and XML deflates extremely well. A text-heavy report often lands at a third to a half of its former size. Documents that are mostly photographs barely move, because the images were already compressed inside the .doc.
The conversion failed. What is the likely reason?
Password protection is the most common cause: an encrypted compound file cannot be read without the password, and there is nowhere to type one here. Open it in Word, remove the protection under File and Info, then try again. The other cause is genuine damage — a .doc truncated by a bad copy or a dying disk often cannot be parsed at all, because the header that maps where the text lives no longer matches the file.
How old can the document be?
Very. The engine reads the Word 97-2003 layout that most .doc files use, and also the older Word 6.0 and Word 95 variants that predate it. The further back you go the more likely it is that decorative elements — early WordArt, the old drawing-canvas objects — get redrawn rather than reproduced exactly, so give an ancient file a quick look before sending it on.
Is there a cost, a sign-up or a watermark?
None of the three. Nothing is stamped onto the converted document and no account is needed. A single upload may be up to 100 MB, which is far beyond anything the binary Word format was ever realistically used to produce.