The network diagram from a sysadmin who left in 2011, the floor plan, the org chart — .vsd to PDF or SVG, no Visio license required.
The libvisio filter reads binary .vsd from Visio 5 through 2010 and the XML-based .vsdx from 2013 onward — stencils (.vss/.vssx) and templates convert the same way if you rename them. Multi-page drawings come through with every page.
PDF for reading, printing and archiving. SVG if you want to keep editing — it opens in Inkscape, Illustrator or the browser, with shapes still shapes and text still text. Neither converts back to editable Visio; for that you’d need Visio itself.
Text, tables and basic formatting come through well; elaborate layouts come through approximately. The engines are the Document Liberation Project filters — two decades of reverse-engineering work, the same ones inside LibreOffice — and they’re the best free readers these formats have. For a file that opens nowhere else, approximate beats gone.
It’s written to a private temporary folder for the few seconds the conversion engine needs, then deleted — nothing is retained, logged or shared. No account, no email, no “files kept for 24 hours” fine print. These are often someone’s letters, family records or old business files; we treat them accordingly.