IrfanView vs Mozilla PDF.js

IrfanView is a Windows graphic viewer with tools for viewing, editing, and processing images. It can convert and process files in batches, rotate and crop JPGs without loss, create slideshows, scan, print, and capture the screen. Editing features include painting tools, effects, watermarking, IPTC editing, and multipage TIFF editing. The maker describes support for many file formats, with plugins adding formats such as AVIF, PDF, SVG, WebP, and camera RAW. Other plugins add OCR, FTP transfer, video playback, Photoshop filters, and PDF support; some require additional software or files. A Shell Extension adds image actions to Windows Explorer and other file managers. IrfanView is listed for Windows XP, Vista, 7, 8, 10, and 11, in 32-bit and 64-bit versions. Private, non-commercial use is free. Commercial use requires a license; the listed single commercial license costs $18 as a one-time purchase and is perpetual. The maker’s privacy policy says the software does not collect or transmit personal data.

Mozilla PDF.js is a free, web standards-based platform for parsing and rendering PDF files. Developers can use its display API to render documents and retrieve information, or adapt the viewer layer for a custom interface. That viewer is used in Firefox and project browser extensions. PDF.js renders annotations and supports adding a subset of annotation types, and it supports form filling; OCR is not provided. The project targets HTML5-compliant browsers and includes a legacy build for older browsers, although PDF feature support varies by browser and version. Prebuilt builds are available, with hosted copies listed through jsDelivr, cdnjs, and unpkg. Developers can clone and build it locally, but some browsers require a local web server instead of opening PDFs through file URLs. Cross-origin requests are blocked by default, so CORS or a server proxy may be needed. For large documents, rendering only visible pages can reduce memory use. PDF.js is licensed under Apache 2.0.