Bigjpg

Bigjpg is a no-frills website for making small images bigger. You upload a picture, choose the style, such as artwork or photo, set the enlargement and noise reduction, and download the larger version. It was one of the early tools built on the waifu2x approach, and it still does a good job with anime, line art and illustrations. The interface is minimal, and the process runs on their servers. Free use is limited in size and queue time, with paid plans for bigger images and faster processing. It suits people who need a quick enlargement and nothing more.