Atomic vs OpenKnowledge

Comparing two open source alternatives to Notion. Use the comparison below to decide which one fits your needs.

Atomic

MIT

A self-hosted personal knowledge base that turns markdown notes into an AI-augmented knowledge graph with semantic search and wiki synthesis.

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OpenKnowledge

GPL-3.0

AI-native, local-first markdown editor and LLM wiki with built-in integrations for Claude, Codex, and other agents.

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Side-by-side comparison

	Atomic	OpenKnowledge
License	MIT	GPL-3.0
Self-hostable	Yes	Yes
GitHub Stars	2,000	4,810
Forks	143	330
Open Issues	36	57
Last Commit	Sep 29, 2026	Nov 6, 2026
First Released	Nov 25, 2025	Jun 3, 2026
Categories	Note Taking & Knowledge Management Tools	Note Taking & Knowledge Management Tools
Tags	#note taking #markdown #knowledge-management #LLM #local ai	#markdown #notes #ai #second-brain #agents

GitHub stars over time

Atomic2,000

OpenKnowledge

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