Hugging Face hosts files packaged for ComfyUI, but of course it also hosts many files intended for other software; sometimes both can even be present in the same repository. The Hub itself does not necessarily make it obvious which exact artifact a particular ComfyUI workflow expects. So if there is a ComfyUI guide, workflow, or template for the model, I think it is usually safer to start from that guide and follow its link to the exact file you need:
I would not try to combine the part1of4.safetensors, part2of4.safetensors, etc. manually yet.
There are a few different things that can look very similar on Hugging Face:
.safetensors shards.
All of those may use the .safetensors file type, so the extension alone does not tell you which one your workflow needs.
The Diffusers documentation on model formats makes this distinction explicitly: Diffusers format and single-file format are different layouts, while safetensors is the file type used to serialize the weights.
My default route would therefore be:
For example, the official ComfyUI Qwen Image example gives exact files such as:
qwen_image_fp8_e4m3fn.safetensors
qwen_2.5_vl_7b_fp8_scaled.safetensors
qwen_image_vae.safetensors
and tells you which ComfyUI directory each one belongs in.
There is also a separate Comfy-Org/Qwen-Image_ComfyUI repository whose model card literally describes the files as “Repackaged model files for ComfyUI” and again lists the appropriate folders.
That is quite different from simply opening the original/upstream model repository and choosing whichever .safetensors file looks closest.
If you still have the page open, I would check it roughly like this:
Do you know the exact filename ComfyUI asks for?
|
+-- Yes
| |
| +-- Is that exact filename linked from a ComfyUI guide/workflow/template?
| | |
| | +-- Yes -> use that link and the directory specified there.
| | |
| | +-- No -> search the exact filename, not only the model name.
| |
| +-- The HF page instead shows model-00001-of-0000N.safetensors?
| |
| +-- Check whether there is also a *.safetensors.index.json.
| If yes, you are probably looking at a sharded model/component,
| not "pieces" that should simply be concatenated.
|
+-- No
|
+-- Go back to the ComfyUI workflow/tutorial first.
Determine:
- the required filename;
- what node consumes it;
- and which models/ directory it belongs in.
The ** node** is also useful information.
A workflow using a normal checkpoint is asking for something different from one a diffusion model, text encoder, and VAE separately.
For example, current ComfyUI examples commonly give instructions of the form:
diffusion model -> ComfyUI/models/diffusion_models/
text encoder -> ComfyUI/models/text_encoders/
VAE -> ComfyUI/models/vae/
while some easier single-file workflows use:
checkpoint -> ComfyUI/models/checkpoints/
The Flux example page demonstrates both styles on the same page.
So if I were troubleshooting this from scratch, I would start with just three pieces of information:
1. The exact filename ComfyUI says it needs
2. The workflow/tutorial/template where that filename appears
3. The Hugging Face page you arrive at
From those three things it should usually be possible to tell whether you are looking at:
I would definitely check that before attempting to merge anything.