PDF to WebP conversion is the process of extracting pages from a PDF (Portable Document Format) document and converting them into WebP image format. This transformation rasterizes the PDF page (which may contain vector graphics, text, and images) into a single WebP image that's optimized for web use.

The conversion process uses Mozilla's PDF.js library to render PDF pages in the browser. Each page is drawn onto an HTML5 Canvas element at high resolution (2x scale for retina displays), then converted to WebP format with customizable quality settings. Unlike server-based converters, all processing happens locally in your browser, ensuring your PDF documents remain private.

When you convert a PDF to WebP, PDF.js first parses the PDF file and extracts the page structure. The selected page is then rendered onto an HTML5 Canvas at 2x scale (192 DPI equivalent) to ensure sharp images on high-resolution displays. This rendering process preserves colors, text, and graphics from the PDF.

The Canvas is then converted to WebP format using the browser's native toBlob() API with the specified quality setting. WebP's advanced compression typically produces files 25-35% smaller than PNG or JPG equivalents, making it ideal for web-based PDF previews, thumbnails, and document sharing.

Note that converting PDF to WebP rasterizes vector content, which means text and graphics become pixels rather than remaining scalable. For best results, use PDFs with clear layouts and sufficient resolution. The tool supports multi-page PDFs, allowing you to convert any page individually with quality control from 10% (smallest file) to 100% (highest quality).