Word to PDF converts a .docx document into a genuine PDF, entirely inside your browser, in two clearly separated steps. First, mammoth reads the document's actual structure — headings, paragraphs, formatting, lists, simple tables — and turns it into clean, semantic HTML. Second, that HTML is mapped into a document definition for pdfmake, which builds a real PDF from it: actual text objects on the page, not a screenshot of one.

That second point matters more than it might seem. A tempting shortcut for this kind of conversion is to render the document to an image and wrap it in a PDF — fast to build, but the result has no selectable or searchable text, defeating much of the point of having a PDF at all. This tool avoids that entirely: pdfmake constructs the output from real text runs, fonts, and layout instructions, so the PDF you download behaves like any other properly authored PDF.

Before the final PDF is built, you'll see a read-only preview of mammoth's extracted HTML — a genuinely useful checkpoint, not just a loading animation. If a heading didn't come through as a heading, or a table looks off, you'll know before waiting on the full conversion rather than after downloading and opening the result.

Complex layouts are the honest limit here. Headings, paragraphs, bold/italic text, simple lists, and simple single-level tables all map cleanly. Nested tables, multi-column sections, text boxes, and embedded images don't have a clean equivalent in this conversion path yet, so a document that relies heavily on those will come through with reduced fidelity rather than failing outright — the goal is always readable output, even when it can't be pixel-perfect.