SlideShift — Free PPT ⇄ PDF Converter

The problem. Every free file converter on the internet makes you upload private presentations to someone else's server — a privacy risk wrapped in paywalls, watermarks, queues, and forced accounts, all for a 10-second task. Desktop suites are heavy overkill, and true conversion normally demands expensive server infrastructure. The solution. SlideShift flips the model: the converter is the webpage. Drop a .pptx and get a clean PDF; drop a .pdf and get a real .pptx — with drag & drop, paste support, quality and layout options, live progress with a per-slide log, and one-click download. Direction is auto-detected from the file, and a conversion counter in localStorage tracks usage without accounts. How it works. Four client-side engines do everything: PDF → PPTX renders each page to an image with PDF.js and places it full-bleed on its own slide with PptxGenJS (16:9 or 4:3). PPTX → PDF unzips the .pptx in-browser with JSZip, reads slides in true presentation order, extracts text and images, and rebuilds a styled PDF with jsPDF. Open DevTools → Network during a conversion: zero file traffic. Files never leave the tab. Honest engineering. This is a content-preserving converter, not a pixel-perfect clone — stated openly on the site: .pptx only (no legacy .ppt), PPTX → PDF keeps text and images but not exact fonts, animations, or charts, and PDF → PPTX slides are faithful images rather than editable text. No password-protected PDFs. Why it matters. Because there is no backend, no database, and no build step — just public/index.html, styles.css, app.js plus CDN libraries — the entire app deploys on free static hosting forever, costs nothing to run, and can't leak your files because it never receives them.