PDF Prompt-Injection Detector

Find text that's invisible to you but readable by LLMs.

Drop a PDF here, or click to choose

Your file is analysed in memory and never stored. PDF only, up to 25 MB.

Don't have one handy?

What it catches

Content stream

Opacity-0, render-mode 3/7, zero-size, off-page, text-rise — including inside form XObjects.

Document structure

Metadata, annotations, form-field values, hidden optional-content layers, attachments, JavaScript.

Render-diff & glyphs

Pixel cross-check that each extracted run is actually painted, plus invisible Unicode and ToUnicode spoofing.