ComfyUI is a modular offline stable diffusion GUI with a graph/nodes interface. It allows you to design and execute advanced stable diffusion pipelines without coding using the intuitive graph-based interface. ComfyUI supports SD1.x, SD2.x, and SDXL, and features an asynchronous queue system and smart optimizations for efficient image generation. It can be configured to work on GPUs or CPU-only, and allows you to load and save models, embeddings, and previous workflows.