isGenAI.com

AI image detector by platform

Facebook AI image detector: label on the post, nothing in the file

Facebook labels images with “AI info” when Meta reads C2PA or IPTC AI indicators in the upload, but the copy you download from Facebook is re-encoded for delivery and normally carries no metadata, so the original file is what isGenAI needs.

Platform behaviour as documented or widely reported in October 2026. Updated .

Check the downloaded imageFrequently asked questions
Controlled example PNG file that carries this record: No record in this copy

without-records.pngPNG file · controlled example

  1. Signature + IHDR
  2. iTXt XML:com.adobe.xmp
  3. tEXt parameters
  4. tEXt prompt / workflow
  5. tEXt invokeai_metadata
  6. eXIf
  7. caBX C2PA manifest
  8. IDAT pixels
  9. IEND

No record in this copy

Screenshots and re-exports often drop records.

A clean copy is not proof of a human author, so the report says what is missing and asks for the original.

Check an image →
Records like these are often removed when a picture passes through Facebook, so the report says what is missing instead of guessing. The picture is a code-drawn controlled example with no records; download it and check it yourself.

What Facebook strips and adds

Meta’s policy for Facebook, Instagram and Threads is the same: read the C2PA and IPTC “AI generated” indicators at upload, label the post, and label Meta AI images that carry Meta’s own markers and metadata. Meta states it cannot identify all AI content and that invisible markers can be removed. Facebook’s delivery copies are resized and re-encoded, and in practice arrive without EXIF, XMP or a manifest.

Images shared inside Facebook from Instagram or Messenger have usually been re-encoded twice.

What isGenAI shows for a Facebook download

The AI image detector reads the file you upload: a C2PA manifest if one survived, the IPTC DigitalSourceType in XMP, AI statements in metadata, saved prompts in the AUTOMATIC1111, ComfyUI and InvokeAI formats, and matching copies by hash and perceptual fingerprint. A platform copy with none of these returns “no evidence found”, and the report says plainly that absence proves nothing about the author.

Keep a screenshot of the label as a separate platform observation; the file report and the platform label answer different questions.

What to do instead

Ask the poster for the original, or trace the first appearance of the image and download from there. The matching-copy check can link a stripped Facebook copy to an earlier file in isGenAI’s records.

If the image is a Meta AI creation, the generator page explains the markers the original carries.

How to check an image from this platform

  1. Note the platform’s own label or credential icon on the post before you download anything; it does not travel with the file.
  2. Ask the poster for the original file, or trace the first upload. A platform download is a re-encoded copy on most services.
  3. Upload what you have to the AI image detector and read the report. A stripped copy returns “no evidence found” honestly.
  4. Use the matching-copy check: a hash or perceptual fingerprint match can tie the stripped copy to an original that still carried records.

Check the downloaded image

Frequently asked questions

Does Facebook strip image metadata?

Facebook serves re-encoded copies that arrive without EXIF, XMP or C2PA records in practice. Meta documents reading those records at upload to label posts, not preserving them in downloads.

What is Facebook’s “AI info” label based on?

C2PA or IPTC AI indicators read in the upload, Meta AI’s own markers, or the poster’s disclosure, per Meta’s announcement.

Can isGenAI detect AI in an image saved from Facebook?

Only from surviving records or a matching copy. Most Facebook downloads return no evidence found; check the original file.

Does a missing label mean the photo is real?

No. Meta states it cannot identify all AI-generated content. Trace the source and check the original.

Sources

Where a platform documents its behaviour, the vendor page is linked. Where it does not, the page says the behaviour is reported, not documented.