Convert ODT to PDF

The document's own layout, kept

ODT is the native format of LibreOffice and OpenOffice Writer, so this is the conversion with the least translation in it — the document is laid out by the software it was written for, and exported. Page size, margins, styles, lists, tables, footnotes and endnotes, headers and footers, floating frames and drawing objects all come out where Writer puts them, and the text stays real selectable text rather than becoming part of a picture.

The export carries structure, not only appearance. Headings with an outline level become the PDF's bookmark sidebar; hyperlinks become real link annotations, with a URL action for web addresses and a page destination for cross-references and contents entries; and the document's title, author and keywords are written into the PDF's own information. A tag tree and the document language go in too, which is what lets a screen reader announce a heading as a heading — a PDF produced by printing to a generic PDF printer usually has none of that.

Fonts are embedded, which is the thing that makes a PDF portable in the first place. The exception is a commercial font whose licence forbids embedding: those are replaced with the closest metric match, so the layout holds and the letterforms differ slightly. Unicode text shaping is fully supported, so Arabic, Bengali, Hindi, Chinese and every other script convert correctly rather than arriving as boxes.

The fallback is a different thing and the page tells you when it runs. If our server cannot be reached, the document is rebuilt locally — keeping text, styles, lists, tables, footnotes and images, while leaving out page headers and footers and placing text boxes in reading order rather than at their exact positions. A plain report converts almost identically; a newsletter built from frames does not.

When you want something else

This one sends your document to a server. Installing LibreOffice and running soffice --headless --convert-to pdf document.odt performs exactly the same export with nothing crossing the network, handles a folder in one command, and has no size limit — the obvious choice for anything confidential or repeated.

For fine control over the export, open the document in Writer and use File → Export as PDF rather than any converter. That dialogue is where PDF/A conformance, tagged output for accessibility, image downsampling, password protection and form-field behaviour actually live — all of them decisions a one-click conversion has to make on your behalf.