Sebastian Kamph explains what ComfyUI is and how it works.
At its core, ComfyUI is a platform where users visually build AI workflows using nodes on a blank digital canvas. A node is a single functional box that performs a specific task, such as loading an AI model, receiving a text prompt, or saving the final image. By drawing lines between nodes to pass data from one to the next, users create a step-by-step workflow. These workflows can range from simple single-image generations to complex, large-scale processes that output images, videos, audio, text, or even 3D assets.
Workflows are commonly saved as standard JSON files. To share a workflow, a user simply sends this file—or even a generated output image containing the embedded metadata—and another user can easily drag and drop it directly onto their own canvas to replicate the setup.
As an open-source, entirely free-to-use program, ComfyUI runs locally on your computer. Its open-source nature allows developers globally to build thousands of “custom nodes” for highly specialized use cases, such as face-swapping or video effects. This unmatched control and customization make ComfyUI the preferred tool for professional studios.