ComfyUI is a powerful and modular stable diffusion GUI and backend that enables users to design and execute advanced stable diffusion pipelines using a graph/nodes/flowchart-based interface. This software supports SD1.x and SD2.x, and provides an asynchronous queue system with many optimizations. It can be used to load ckpt, safetensors, and diffusers models/checkpoints, as well as standalone VAEs and CLIP models. Other features include embeddings/textual inversion, area composition, inpainting with both regular and inpainting models, ControlNet and T2I-Adapter, upscale models, unCLIP models, and more. ComfyUI starts up quickly and works fully offline without downloading anything. Users can also save and load workflows as Json files, and the nodes interface can be used to create complex workflows.