PaperOtter is a desktop app with 19 document tools, all running on your own machine. Compress a PDF to a size you name, merge, split, rotate, sign, redact and repair, and convert PDFs or Word files into Markdown, HTML or JSON with headings and lists intact, which makes them far cheaper to feed to an LLM. Nothing is uploaded: there is no network code in the document paths at all. Free, open source, offline and no account, for Mac, Windows and Linux.