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PNG Metadata: the AI Prompt and Text Chunks Inside

PNG is a lossless format used for screenshots, graphics, and increasingly AI-generated art. Unlike a JPEG it almost never carries GPS or a camera serial, but it has its own tell: image generators write the entire recipe that made the picture into a plain-text chunk that travels with the file. If you share an AI PNG, you are usually sharing the prompt.

Scan a PNG file

What a .png file reveals

The generation recipe is what makes a PNG distinctive. Locally-run generators (Automatic1111, Forge, ComfyUI, NovelAI) embed the full prompt, the negative prompt, the model checkpoint, the sampler, the seed, the CFG scale and every LoRA into tEXt, zTXt and iTXt text chunks, in cleartext. File X-Ray reads them, including the zlib-compressed ComfyUI workflow graph, and names the generator. A viewer shows none of it; the recipe to reproduce the image is simply sitting inside the file.

PNG's text chunks double as identity. tEXt is where Author, Copyright, Software and Creation Time live, the same identity fields a JPEG keeps in EXIF. Any editor that wrote them, plus a proprietary producer chunk some tools leave behind, name the software pipeline that made or last touched the picture.

Structure a viewer hides also surfaces. An Apple iDOT chunk marks the file as an iOS screenshot or a Photos/Preview export, fingerprinting an Apple device even when no EXIF survives. An animated PNG (APNG) holds more frames than the single image you see. An ImageMagick virtual-canvas (vpAg) chunk records the larger dimensions the picture was cropped from. A stereo (sTER) chunk marks a side-by-side 3D pair. Each one is reported in the scan.

What a PNG usually does not have is worth stating plainly. A plain PNG rarely carries GPS or a maker-note serial, because PNG was never a camera capture format, so if location is your worry a PNG is far less likely to leak it than a JPEG or HEIC. XMP and an ICC colour profile can still be present, and data appended after the final IEND chunk is flagged as a possible hidden payload.

Key fields

Generation Prompt
The text prompt used to create an AI image, stored in cleartext in a PNG text chunk.
Negative Prompt
What the generator was told to avoid, stored right alongside the prompt.
Generation Parameters
The model checkpoint, sampler, seed and CFG scale recorded in the recipe.
LoRAs Used
The fine-tune adapters applied to the model, named in the recipe.
AI Image Generator
Which tool wrote the recipe: Automatic1111, ComfyUI, SwarmUI or NovelAI.
Text Chunks (Author / Software / Creation Time)
Identity and tool fields PNG stores in tEXt instead of EXIF.
Apple Imaging Pipeline (iDOT)
Marks the PNG as an iOS or macOS screenshot or export.
Pre-Crop Canvas (vpAg)
The larger dimensions the image was cropped or trimmed from.
Animated PNG (APNG)
Extra hidden frames beyond the single static image a viewer shows.
ICC Colour Profile
The embedded colour space (Display P3, sRGB, Adobe RGB).

This is a selection. The full field manual documents the fields read from each format.

Questions about PNG metadata

Does a PNG contain the AI prompt used to make it?

If it was generated by a local tool like Automatic1111, ComfyUI or NovelAI, almost always yes. Those tools write the full prompt, model, sampler, seed and LoRAs into a PNG text chunk in plain text, and it stays there when you share the file. Drop the PNG here to see the whole recipe.

Does a PNG have EXIF or GPS like a photo?

Usually not. PNG was designed for graphics and screenshots, not camera capture, so it rarely holds a GPS location or a camera serial. It can still carry XMP, an ICC profile, and text chunks with an author or software name.

How do I remove the metadata and prompt from a PNG?

Re-save it through a tool that rewrites the file without ancillary chunks, or use the clean copy this page generates: it drops the text chunks holding the prompt while leaving the picture itself identical.

Can a PNG screenshot reveal what device I used?

It can. An Apple iDOT chunk marks the file as an iOS or macOS screenshot or export, and a Software text chunk or producer chunk names the app that saved it, so even a plain screenshot can fingerprint your platform.

What is an APNG and why does it matter for hidden content?

An animated PNG stores several frames while looking like a normal PNG to most viewers, so frames beyond the first, which can include a pre-edit version, travel with the file unseen. The scan reports the frame count.

File X-Ray reads PNG files entirely in your browser - the file never leaves your device. For this format you can also download a clean copy with the metadata removed. Scan a file now.

All supported formats