IrfanView is described as 'Fast and powerful image viewer, editor, and converter for beginners and pros. Supports various formats, batch processing, and many extensions' and is a leading Image Viewer in the photos & graphics category. There are more than 100 alternatives to IrfanView for a variety of platforms, including Windows, Linux, Mac, Flathub and Web-based apps. The best IrfanView alternative is XnView MP. It's not free, so if you're looking for a free alternative, you could try XnView MP or nomacs. Other great apps like IrfanView are ImageGlass, XnView Classic, JPEGView and qView.
Fast, compact, responsive, so many features like batch conversion, screen capture, image compression, etc., definitely this is a amazing tool.