ChatGPT accepts PDFs natively, but the experience is hit-or-miss: scanned pages fail, tables flatten, and a long document burns through context fast. Converting to Markdown first gives ChatGPT clean input it can actually reason over.
ChatGPT's built-in PDF reader extracts text under the hood, but you don't see what it extracted — and that's the problem. Tables sometimes come through as comma-separated soup; columns interleave; footnotes land mid-paragraph. Convert the PDF to Markdown yourself and you can read the output, fix anything weird, and paste a clean version in. The token count also drops because the Markdown version drops the PDF's layout overhead. On a 50-page report that's the difference between fitting in one conversation and bumping into context-window limits halfway through.
Drop your PDF on t0md, hit Copy, paste into ChatGPT. If the document has tables or footnotes you care about, give the Markdown a quick scan before pasting — it's a few seconds to fix anything that didn't survive. For repeat use, install the t0md MCP server in any MCP-compatible client and the conversion happens inside the conversation. ChatGPT itself doesn't speak MCP yet, so the copy-paste flow is the path there.
You can, but you lose visibility into what ChatGPT actually extracted. With a Markdown intermediate, you see exactly what the model is seeing — which makes debugging bad answers much easier.
Yes. The Markdown is plain text — paste it into any ChatGPT tier. Free-tier users get the bigger benefit since attached-file behaviour varies by plan.
Usually — Markdown is significantly more compact than the PDF's layout overhead. For documents that still overflow, split on headings and feed sections in turn, or use a RAG pipeline instead.