comfyui

TLDR

Start ComfyUI server

$ python [main.py]

Start on specific port

$ python [main.py] --port [8188]

Start with CPU only

$ python [main.py] --cpu

Start in headless mode (API only, no browser)

$ python [main.py] --dont-print-server

Use specific GPU

$ python [main.py] --cuda-device [0]

Run with low VRAM mode

$ python [main.py] --lowvram

Execute a workflow via API

$ curl -X POST http://localhost:8188/prompt -H "Content-Type: application/json" -d @[workflow.json]

SYNOPSIS

python main.py [options]
comfyui [options]

ComfyUI is a node-based workflow system for Stable Diffusion and Flux image generation. It provides both a visual graph editor (web UI) and a REST API for programmatic use.
Workflows are built by connecting nodes: model loaders, samplers, VAE decoders, prompt encoders, and more. Complex pipelines (img2img, inpainting, ControlNet, LoRA stacking) are constructed visually without code.
The API accepts workflow JSON, enabling headless batch generation and integration with scripts. Workflows created in the web UI can be exported and run via the API.
An extensive ecosystem of custom nodes adds capabilities: video generation, face restoration, upscaling, IP-Adapter, and more. Custom nodes are installed into the `custom_nodes/` directory.
Install via pip (`pip install comfyui`) or clone the repository. Models are placed in the `models/` directory tree.

PARAMETERS

--port PORT

Server port (default: 8188).

--listen ADDR

Listen address (default: 127.0.0.1, use 0.0.0.0 for network).

--cpu

Run on CPU only.

--cuda-device ID

CUDA GPU device index.

--lowvram

Low VRAM mode for GPUs with limited memory.

--dont-print-server

Suppress server output.

--output-directory DIR

Custom output directory.

--temp-directory DIR

Custom temp directory.

--auto-launch

Auto-open browser on start.

--disable-auto-launch

Prevent auto-opening browser.

CAVEATS

Web UI requires a modern browser. GPU strongly recommended. Custom nodes may conflict. Model files are large (2-10+ GB each). Python 3.10+ required. Complex workflows can consume significant VRAM.

HISTORY

ComfyUI was created by comfyanonymous in 2023 as a modular alternative to the Automatic1111 web UI. Its node-based design attracted power users who needed flexible, reproducible generation pipelines. It became one of the most popular Stable Diffusion interfaces, with a large community building custom nodes.