ComfyUI EXIF Explained: Where Prompt and Workflow Metadata Actually Live
“ComfyUI EXIF” is common search shorthand, but the useful generation data is usually stored in PNG text chunks, not camera EXIF. This guide explains where prompt and workflow JSON live, what each chunk means, what removes them, and how much evidentiary weight they deserve. To view a file’s prompt and workflow JSON right away, open the free PNG Parameter Extractor—it reads the chunks in your browser without uploading the image.
The answer: check prompt and workflow PNG chunks first
An original ComfyUI PNG commonly carries prompt and workflow keys inside tEXt, iTXt, or zTXt chunks. The values can include the node graph, checkpoint or model name, seed, sampler, scheduler, steps, CFG, width, and height. These chunks are unsigned and editable, so they explain how a file was made but do not provide tamper-evident proof.
Extract ComfyUI workflow metadata →Guide page or extraction tool?
| This platform guide | Learn where ComfyUI stores metadata, why it is not camera EXIF, what survives sharing, and how to interpret the evidence. |
|---|---|
| PNG Parameter Extractor | Upload an original PNG, search prompt/workflow fields, copy a safe summary, and export the raw JSON. |
Real sample and verified parser output
| ComfyUI / Stable Diffusion XL PNG | An original PNG from the official ComfyUI examples is bundled in the public sample set. |
|---|---|
| Fields found | Readable prompt and workflow text chunks, full unsigned workflow JSON, node graph data, model references, and generation settings. |
| Evidence level | Strong descriptive provenance, but lower confidence than a valid C2PA signature because the chunks can be edited or copied. |
What each ComfyUI field tells you
| prompt | Serialized node inputs and generation parameters. It often includes class_type values and model or sampler settings. |
|---|---|
| workflow | The graph layout, nodes, links, and UI structure that can often be loaded back into ComfyUI when the original export is intact. |
| Model and sampling fields | Checkpoint or model file names, seed, sampler, scheduler, steps, CFG, width, and height when preserved. |
| Raw PNG text | The original tEXt, iTXt, and zTXt values. They may contain prompts, file paths, or custom-node details that should be reviewed before sharing. |
Why an EXIF-only reader can miss everything
EXIF is a camera-oriented tag system for fields such as exposure, ISO, aperture, and lens data. A multiline prompt or serialized node graph does not fit that model. PNG text chunks accept arbitrary key-value content, so ComfyUI uses them instead. A file can therefore contain a complete workflow while an EXIF-only tool reports nothing.
What preserves the workflow—and what removes it
Copying or moving the original PNG usually preserves the chunks. Converting to JPEG, taking a screenshot, re-exporting through a non-preserving editor, or uploading to a service that re-encodes the image commonly removes them. An empty result means this copy carries no readable workflow; it does not prove the image was not made with ComfyUI.
How to inspect a ComfyUI PNG without losing evidence
- Keep the direct export: Use the PNG written by ComfyUI, not a screenshot, JPEG conversion, or social-media download.
- Open the PNG Parameter Extractor: The file is parsed locally in the browser and is not uploaded.
- Check prompt and workflow: Confirm which chunks exist before reading model, seed, sampler, CFG, and node details.
- Review the raw JSON carefully: Large workflows can contain prompts, paths, and custom-node information that may be sensitive.
- Interpret it as unsigned evidence: A preserved workflow is highly informative, but it can be edited and is not equivalent to a signed credential.
Limits
- Prompt and workflow chunks are unsigned and can be edited, removed, or copied to another image.
- Screenshots, JPEG conversion, social-media re-encoding, and many optimizers remove PNG text chunks.
- Custom nodes and extensions may write fields that cannot always be normalized into friendly labels.
- No workflow found means only that this copy has no readable workflow data.
FAQ
- How do I view ComfyUI metadata from a PNG?
Open the original PNG in the PNG Parameter Extractor. It reads the prompt and workflow chunks locally and shows the prompt, workflow JSON, model, seed, sampler and CFG. Nothing is uploaded.
- Is ComfyUI metadata really EXIF?
Usually not. The important generation data is commonly stored in PNG text chunks named prompt and workflow, separate from camera EXIF tags.
- Can I recover the exact ComfyUI workflow?
Often yes when the original PNG preserved the workflow chunk. Custom nodes and external models may still need to be installed separately.
- Why is workflow metadata weaker than C2PA?
It is unsigned and editable. A valid C2PA manifest can detect tampering; a ComfyUI workflow mainly explains the production process.
- How do I stop ComfyUI from saving metadata?
Start ComfyUI with the --disable-metadata launch flag and saved images will no longer include the prompt and workflow chunks. For a file you already exported, converting it to JPEG or re-saving it in an editor that drops PNG text chunks removes them; check the result in the extractor afterwards.
- Is the PNG uploaded?
No. Parsing runs locally in your browser.
Related tools and guides
Sources and verification records
- Official ComfyUI examples — Source of the bundled SDXL workflow PNG.
- AICheck365 public sample records — Sample origin, test date, observed signals, and known limits.
- W3C PNG Third Edition — Standard reference for PNG chunks and text storage.
- AICheck365 methodology — How unsigned metadata is weighted against signed provenance.