Image to PDF: when this matters
Government forms, expense reports, and applications almost always ask for a single PDF — not a folder of photos. Pulling multiple receipts, scans, or screenshots — in PNG, JPG, or JPEG — into one PDF makes them easy to email and sensible to file. Pick Auto-fit page size to make each PDF page match its image, or pick A4 / Letter for a uniform document that prints cleanly.
PDF to Image: when this matters, and which format to pick
Sometimes you need an image of a PDF page — to paste into a slide deck, embed in a Notion page, share on social media, or open with a basic image viewer. The exporter renders each page at 2× device resolution (great for retina screens) and lets you choose the output format: JPG for a smaller file, best for photos and scanned pages, or PNG for a lossless image, best for text-heavy pages, diagrams, and screenshots where compression artefacts would blur small text.
Privacy
Both directions run in your browser. Image to PDF uses pdf-lib to embed PNG or JPEG images directly into a new PDF. PDF to Image uses pdfjs (Mozilla’s PDF renderer) to draw each page to a canvas, then exports the canvas as a JPG or PNG. Nothing is uploaded.