digiKam - Professional Photo Management with the Power of Open Source
IrfanView - IrfanView ... one of the most popular viewers worldwide.
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
ImageGlass - You can use Image to view your digital images and photos of many different formats.
Photos on macOS - Photos keeps your images organized and accessible. Rediscover favorite shots with Memories. Access them on your devices with iCloud Photos.
Movavi Photo Manager - Focus on the memories, forget about managing photos