Image Upscaler enlarges photos up to 4x and recovers blur entirely inside your browser — your files never touch a server. Pick the standard mode for a result in about a second, or the AI super-resolution mode (Swin2SR, running on WebGPU) for finer detail. Both are shown side by side with your browser's own enlargement, so you can compare before you save. Free, no sign-up, no watermark.