Logseq

Open-source knowledge base with a privacy-first stance. All data lives locally in plain text, either Markdown or Org mode, never primarily in the cloud. A direct competitor to Obsidian, but with a different mental model: block-based rather than document-based.

What Makes It Distinct

Logseq thinks in blocks instead of files. That means bidirectional links work not only on the page level, but on the paragraph level. One specific block from one note can reappear in another note while preserving context.

Features include:

• Queries - SQL-like filtering across notes
• Flashcards - built-in spaced repetition generated from notes
• PDF annotation - annotate PDFs and reference the annotations as blocks
• Whiteboards - infinite canvas for visual arrangement

Compared with Obsidian

Logseq and Obsidian share the same deeper philosophy: local files, Markdown, and bidirectional links. The difference is the mental model:

• Obsidian is document-centered
• Logseq is block-oriented

People who live in daily notes and ongoing capture often prefer Logseq’s structure. People who curate durable thematic pages often find Obsidian clearer.

Connections

• Obsidian - direct comparison; same philosophy, different interaction model
• File over App - both tools follow it

Sources

• A privacy-first, open-source knowledge base - Logseq context (2026-04-06)