Stable Diffusion WebUI by AUTOMATIC1111 is an open-source browser interface for running and controlling Stable Diffusion image-generation models. Built with Gradio, it turns the underlying diffusion workflow into a feature-rich graphical environment for generating and editing images without requiring users to operate everything directly through Python scripts or command-line tools.

The interface supports core workflows such as text-to-image, image-to-image, inpainting and outpainting, along with extensive control over prompts, negative prompts, sampling methods, seeds, image dimensions, high-resolution generation, and generation parameters. It also includes tools for face restoration, upscaling, checkpoint management, prompt weighting, batch processing, embeddings, hypernetworks, LoRAs, and model training-related workflows.

One of the project's major strengths is its extensibility. Community extensions and custom scripts can add new workflows and capabilities, while an API enables integration with other software. The WebUI supports a range of hardware configurations and has become a flexible environment for users who want detailed local control over Stable Diffusion models and image-generation settings.