Your settings travel with the image
Local generators store their settings as text inside the output so an image can be recreated. In PNG files that text sits in tEXt, zTXt or iTXt chunks alongside the image data. What you will typically find:
- A1111 and Forge: a “parameters” chunk with prompt, negative prompt, steps, sampler, CFG, seed, resolution, model hash and name, plus LoRA and extension settings.
- ComfyUI: a “prompt” chunk holding the executed node graph and a “workflow” chunk holding the full editor layout — drop the PNG into ComfyUI and the whole setup reappears.
- InvokeAI, NovelAI and other front-ends: similar data under their own keys.
- JPEG or WebP exports: some tools write the same text to EXIF UserComment instead.
Reasons to wash it — and reasons not to
Generation data is a full recipe. It lets anyone reproduce your look, shows which checkpoints and LoRAs you rely on, and can expose local paths, folder names or usernames buried in a workflow. Big ComfyUI graphs can also add tens of kilobytes per image.
On the other hand, model-sharing sites read the parameters to display generation info, and collaborators may want the workflow. Check each file first; AI Label Remover shows everything before removing anything.
Reading the prompt in AI Label Remover
Lay the PNG on the table. In “Raw metadata” each text chunk appears under its keyword — parameters, prompt, workflow — with its full contents, while the “AI traces” tab flags it as a Stable Diffusion prompt or ComfyUI workflow. Compressed zTXt and iTXt chunks are inflated in the browser so you can read them.
What washing keeps
Press “Wash all images”. The PNG handler drops text, XMP, EXIF and C2PA chunks as whole units and keeps IHDR, IDAT, palette, transparency, gamma and color chunks, as well as APNG animation chunks. Because chunks are removed whole, the remaining CRCs stay valid and the file opens everywhere. The PNG metadata remover page covers each chunk in detail.
Opening and re-saving in an editor would also lose the text, but it re-compresses the image and can shift colors. Byte-level removal avoids both.
About Stable Diffusion and ComfyUI data
How do I stop A1111 or ComfyUI from saving metadata?
A1111 and Forge have a setting that stops writing generation parameters into PNG files, and ComfyUI can be started with the --disable-metadata flag. Both apply only to new images, so wash the ones you already have.
Can ComfyUI rebuild the workflow from a washed PNG?
No. The “prompt” and “workflow” chunks are gone, so dragging the file into ComfyUI restores nothing. Keep an unwashed original if you will need the graph again.
Is the washed PNG identical to look at?
Yes. The IDAT chunks holding the compressed pixels are copied unchanged, so the image is pixel-for-pixel the same.
What about JPEG and WebP exports?
Prompts stored in EXIF UserComment or XMP are detected and washed out of JPEG and WebP files too.