Last updated 2026-04-24 · 2 min read

PDF not working

PDFs with a real text layer work great. Scanned-image PDFs are hit or miss — Gist reads the pages as images. Protected and very large PDFs are the other common failure modes.

PDFs come in three kinds. Which one yours is determines how well Gist reads it.

1. Text-layer PDF — works great

Created from a Word doc, a typeset paper, or a modern PDF export. You can select the text with your cursor and paste it elsewhere. Quality matches regular web articles.

2. Scanned-image PDF — hit or miss

A scan of a paper document is a series of images, even if it looks like text. If you cannot select any text in the PDF, it is a scanned-image PDF.

There is no text layer to extract, so Gist falls back to handing the pages straight to the AI model, which reads them as images. A clean, high-resolution scan often comes through fine; a faint, skewed, or handwritten one may come back wrong or empty. If a scan does not work, export a text-layer version first (most modern scanners and PDF editors can do this) and upload that instead.

3. Protected or gated PDF — fails

Passwords, DRM, or copy-locks block reading. Gist will say the file is not readable.

What to try

  • Select text in the PDF. You cannot? It is scanned — Gist will try to read the pages as images, but quality varies. If the Gist comes back wrong, re-export as a text-layer PDF or paste the content directly into /try.
  • Try /try with a file upload. Drag the PDF in and let it run — the cleanest path for local PDFs.
  • Upload the original document instead. If you have the source file (Word, PowerPoint, HTML, etc.), upload that directly. Gist now accepts PDF, DOCX, XLSX, PPTX, HTML, CSV, TXT, Markdown, AsciiDoc, LaTeX, and XML.
  • Break up huge PDFs. Book-length PDFs can hit limits; try a chapter at a time via /try.
  • Export a cleaner version. If you control the PDF, re-export as a text-layer PDF and try again.

When to contact support

A text-layer PDF — one where you can clearly select text — failing or producing a wrong Gist is a bug. Send it via contact support:

  • The PDF itself (if you can share), or a link.
  • What you expected vs. what you saw.
  • Whether it is a paper, book chapter, report, etc.

What is next

Related