OneNote Markdown Exporter

In .NET Tags #open-source #utilities Published 4/4/2026

OneNote Markdown Exporter

DiggingOut.png

Export your Microsoft 365 OneNote notebooks into clean, GitHub‑Flavored Markdown — with hierarchy, metadata, images, and attachments preserved — using the Microsoft Graph API.

Because your notes deserve better than being trapped in a proprietary format forever.

🚀 What This Tool Does

  • Authenticates via Microsoft Graph (delegated user auth)
  • Walks your entire OneNote hierarchy (notebooks → sections → pages)
  • Downloads page content as HTML
  • Converts it to GitHub‑Flavored Markdown
  • Saves images and attachments
  • Writes YAML front matter for easy static‑site or GitHub‑wiki use
  • Supports incremental exports so you can run it again without reprocessing everything

If you have ever thought, “Why is there no official OneNote export tool?” — this is that tool.

📦 Prerequisites

  • .NET 8 SDK
  • A Microsoft 365 account with OneNote content
  • Your OneNote notebooks are synchronized to OneDrive
  • An Azure AD app registration (instructions below)
  • (Optional) Pandoc (pandoc.org in Bing) if you want the heavyweight HTML→Markdown conversion engine

If that has not scared you off, you can get it from GitHub.

🎉 Final Notes

This project exists because exporting OneNote should not require ritual sacrifice, manual copy‑paste, or a PhD in patience. If this tool saves you even one hour of your life, consider starring the repo — or telling someone else who is trapped in OneNote purgatory.

Leave a comment

Please note that we won't show your email to others, or use it for sending unwanted emails. We will only use it to render your Gravatar image and to validate you as a real person.