Word to PDF

How do I convert a Word document to PDF?

1. Drop one or more .docx files onto the drop zone, or click it to choose them.
2. Under Page size, choose A4 or US Letter.
3. Click Convert to PDF.
4. Download the PDF, or click Download all as ZIP if you converted several documents.
5. Open the PDF and check headings, lists and page breaks before sharing it.

Word to PDF unpacks the .docx file in your browser (a .docx is a ZIP of XML files), reads the document structure and lays the content out on fresh PDF pages with pdf-lib. Headings are set larger and bolder, paragraphs keep their breaks, bold and italic runs are honoured and bulleted and numbered lists are indented. Text flows onto as many pages as it needs. The result is a real text PDF, so it stays selectable, searchable and small: a 20-page letter typically comes out under 200 KB.

Page size matters mostly for printing. A4 is 210 × 297 mm and is the standard in the UK, Europe and most of the world; US Letter is 216 × 279 mm and is used in the United States and Canada. Pick the size your reader will print on, because text that fits A4 nicely can fall differently on the slightly shorter, wider Letter page. Page breaks happen where the text runs out of room, not where Word placed them, so pagination may differ from what you saw in Word.

This is a lightweight converter, not a copy of Word's layout engine. Images are simplified or dropped, tables are flattened into their text, and custom fonts are replaced with a standard PDF font. Headers, footers, footnotes, text boxes and tracked changes are not reproduced. If a document depends on precise layout, such as a CV with two columns or a brochure, export it from Word or LibreOffice directly and use Kilnfile for the follow-up jobs like compressing, merging or protecting the PDF.

Only .docx files are accepted. Older .doc files from Word 2003 and earlier need to be saved as .docx first, which Word, LibreOffice and Google Docs can all do. There is no file size limit beyond device memory, no signup and no watermark, and because the conversion runs on your device the document is never uploaded or stored anywhere.

How it works: this tool uses pdf-lib and PDF.js (Mozilla), open-source libraries loaded into your browser. No server is involved, so Kilnfile never sees your file. Last reviewed 20 September 2026.

Frequently asked questions