Free AI Video Upscaler (In-browser)
A free, open-source tool that upscales video and images entirely inside your browser. It ports upscaling algorithms such as Anime4K and RealESRGAN to WebGPU, so your file is never uploaded to a server. The site notes it works particularly well on animated content.
How to try it
Click 'Choose a video or image file', pick a model size from Small, Medium, Large or XL, then press 'Start upscaling' to watch the progress. When it finishes, use the 'Tap to compare' slider to check the result against the original and download it; the language list at the top includes Korean. It needs WebGPU, so a recent desktop Chrome or Edge is required and it will not run on mobile — and the tab must stay open until processing ends.