ComfyUI

ComfyUI is a graph/node based engine for designing and executing generative AI pipelines. The project began as a Stable Diffusion image generator and has grown into a general-purpose runtime for image, video, audio, and 3D models, with built-in support for dozens of model families. It runs as a local Python application that exposes an HTTP and WebSocket API plus a separate web frontend.

The repository at comfyanonymous/ComfyUI is the core: the Python runtime, the diffusion engine, the prompt executor, the model loaders, the built-in nodes, and the web server. The frontend (Vue/TS) lives in Comfy-Org/ComfyUI_frontend and is shipped as a compiled bundle under web/. The desktop application lives in Comfy-Org/desktop.

What it does

A user defines a workflow as a directed graph of nodes (load checkpoint → encode prompt → sample → decode → save image). The frontend serializes the graph as JSON and POSTs it to /prompt. The backend validates the graph, schedules nodes for execution, and runs them. Node results are cached so re-running the same prompt only re-executes nodes whose inputs changed. Sampling progress and previews are streamed back over a WebSocket.

Where to start

If you want to…	Read…
Install and run ComfyUI	Getting started
Understand how the pieces fit together	Architecture
Look up a project-specific term	Glossary
See a quantitative snapshot of the codebase	By the numbers
Learn the history and major rewrites	Lore
Contribute code	How to contribute
Understand the prompt executor	Prompt execution
Understand model loading and memory management	Model management
Browse the in-tree Python packages	Packages
Build a custom node	Custom-nodes system
Use the HTTP API	API

Sibling repositories

ComfyUI Core is one of three coordinated repositories:

graph LR
    Core[comfyanonymous/ComfyUI<br/>this repo] -->|frontend bundle pinned in requirements.txt| Frontend[Comfy-Org/ComfyUI_frontend]
    Core -->|workflow templates pinned in requirements.txt| Templates[Comfy-Org/workflow_templates]
    Desktop[Comfy-Org/desktop] -->|builds against latest stable| Core
    Manager[Comfy-Org/ComfyUI-Manager] -.optional, --enable-manager.-> Core

Frontend and template versions are pinned in requirements.txt (comfyui-frontend-package, comfyui-workflow-templates, comfyui-embedded-docs).

Project status

• Version: 0.20.1 (defined in pyproject.toml and mirrored in comfyui_version.py)
• License: GPL-3.0 (LICENSE)
• Python: 3.10+ required, 3.12/3.13 recommended
• Release cadence: roughly weekly stable tags, nudged by model releases