About the DOC format
DOC is the binary format of Word 97 to 2003. Many old letters, templates, CVs and archives are still in DOC. Opening them can be tricky without Office, and newer apps sometimes show them incorrectly. A PDF preserves the document in a fixed form that anyone can open, print and archive.
Things to check
LibreOffice handles DOC files well, but very old documents with macros, embedded objects or fonts that are no longer installed may look slightly different. Check page breaks and tables in the PDF. Macros don’t run in PDFs. Everything is processed on your device, so even sensitive archives stay private.
How to convert
Choose or drop the DOC above; the office page opens automatically. Click “Convert” and download the PDF. The first time, LibreOffice (about 77 MB) is downloaded into your browser; later it starts instantly.