ComfyUI vs. Automatic1111 Stable Diffusion WebUI

ComfyUI and Automatic1111 Stable Diffusion WebUI (Automatic1111 WebUI) are two open-source applications that enable you to generate images with diffusion models.

Both are superb in their own right.

However, they are both very different when it comes to using them.

Automatic1111 WebUI is terrific for simple image generation, retouching images (inpainting), and basic controls. It’s more beginner-friendly.

On the other hand, ComfyUI is more performant and provides much greater control to the end-user. However, it requires a deeper understanding of how diffusion models work and is better for intermediate to advanced users.

💻 The Interface

Here’s an overview of how each of these applications looks:

Right away, you can see the differences between the two. In Automatic1111, you can see its traditional design is separated into various tabs where you start to generate images.

Whereas in ComfyUI, each of the nodes are essentially different parts of the interface strung together (checkpoint, positive prompt, negative prompt, etc.).

This means that you’ll need a basic understanding, just at a high level, of how an image is generated with a diffusion model. But as you will likely quickly learn, this offers superior flexibility for image/video generation.

🤗 Community Support

The open-source community for both applications is outstanding. Every day, I feel like I am learning of a new extension or script that makes both of these applications even better.

Automatic1111 WebUI in total has 305 different extensions available. You can view the .json file of all available extensions here.

The Automatic1111 repository also has a lengthy list of extensions with a short explanation of their capabilities here.

ComfyUI has what they call custom nodes. To date, there are 1251 different custom nodes! The .json file that contains all of these nodes is available in the ComfyUI Manager repository — which itself is a custom node that is used to install other custom nodes.

Needless to say, both are well-supported by the community.

📈 Performance

For a non-scientific comparison, I ran a batch of 20 images through both ComfyUI and Automatic1111 WebUI to see what the total time was for each.

The images were based on the Stable Diffusion 1.5 model and at a resolution of 512×768. For reference I am using a RTX 3060 (12GB VRAM).

Here are the results:

ComfyUI ——– 1:07

Automatic1111 WebUI ——– 2:23

A total time difference of 1:16 is quite significant.

When doing video generation, this time difference will be even more pronounced as you render each frame.

Now, there are definitely tweaks and optimizations that can be done with Automatic1111 WebUI to improve performance. But out of the box, ComfyUI is the clear winner.