Notion is a database. Markdown is a file format. This sounds like a trivial distinction, but it is the single most important decision in choosing a knowledge tool. It determines what happens to your notes when the company changes pricing, when the API deprecates, or when you simply want to leave. For a direct feature comparison, see our Glassy vs Notion page.
The lock-in spectrum
Vendor lock-in is not binary. It is a spectrum from "your data is trapped in a proprietary format that no other tool can read" to "your data is plain text files that any editor can open." Notion and Obsidian sit at opposite ends.
Notion stores your content in a proprietary database. The block-based editor produces structured JSON, not text. You can export to Markdown, but the export is lossy — databases become tables, relations become plain text, embedded views disappear, and file attachments are downloaded as a separate zip. The export is a snapshot, not a live format.
Obsidian stores every note as a plain Markdown file in a local folder. You can open the folder in VS Code, grep it from the terminal, sync it with Git, or copy it to a USB drive. The format is an open standard. If Obsidian shuts down tomorrow, your notes are fine.
The export test
The real test of lock-in is not whether you can export. It is whether the export is useful. Let's be honest about what happens when you export from each tool:
Notion export
- Markdown files with broken internal links (page references become plain text)
- Databases export as CSV or Markdown tables — relations and rollups are lost
- Embedded content (Figma, YouTube, Google Drive) becomes URLs
- File attachments download separately and links break
- No frontmatter, no tags, no metadata survives
- The result is readable but not structured — you lose the knowledge graph
Obsidian / Glassy export
- Markdown files with intact wikilinks
[[like this]] - Frontmatter and tags preserved in YAML
- Backlinks are just wikilinks — they work in any Markdown editor
- Files are already on your disk — "export" is just copying a folder
- Any tool that reads Markdown can index, search, and render your notes
Why this matters in 2026
In 2026, the AI layer makes portability matter more, not less. When you connect your knowledge base to Claude Desktop, Cursor, Windsurf, OpenCode, Hermes, Openclaw, Pi, or any MCP-compatible AI agent via MCP, or when you run semantic search across your notes, the AI needs structured text. Markdown is native input for every LLM. Notion's JSON blocks are not.
Notion shipped an official MCP server in 2026, and it works — but it translates blocks to Markdown on the fly, which adds latency and token overhead. Obsidian has 64+ community MCP servers because the format is already what LLMs want to read.
The middle path
Glassy is built on Markdown. Every note, bookmark, and document is stored as a Markdown file. But Glassy also provides the things Obsidian does not: a hosted web interface, browser extension capture, local AI, voice transcription, and a built-in MCP server.
You get the portability of Markdown with the convenience of a modern web app. And if you ever leave Glassy, your data exports as the same Markdown files you would have had if you had used Obsidian directly. No lossy conversion. No broken links. No proprietary format.
When Notion is still the right choice
Notion is not evil. It is a good tool for specific use cases:
- Team wikis where real-time collaboration on structured databases matters
- Project management with Kanban boards, timelines, and relations
- Companies where Notion is already the institutional standard
But for personal knowledge management — your second brain, your research, your half-formed ideas — portability is non-negotiable. Your notes outlive tools. They should outlive Glassy too.