Obsidian is a free, local-first knowledge base and note-taking app that stores every note as a plain Markdown file on your own device. We rate it 91/100 — it is the best personal knowledge management (PKM) tool in 2026 for anyone who wants full data ownership, a keyboard-first workflow, and a plugin ecosystem large enough to turn one app into a writing studio, a CRM, a Zettelkasten, or a project tracker. It is the wrong pick only if you need real-time multi-user collaboration out of the box.

What is Obsidian?

Obsidian was built by Shida Li and Erica Xu, the same Waterloo duo behind the outliner Dynalist. The two began the project during the first weeks of the COVID-19 lockdown and shipped the first public beta on March 30, 2020. Version 1.0 arrived on October 13, 2022, and the current stable line — Obsidian 1.9 — shipped throughout 2025 and 2026, adding the Bases core plugin that turns any folder of notes into a filterable, formula-driven database. The company is still fully bootstrapped, has never taken venture funding, and founder Steph Ango has publicly said that even the founders don’t know the exact user count — community estimates put monthly active users at roughly 1.5 million as of late 2025, with over 110,000 members in the official Discord.

The specific problem Obsidian solves is vendor lock-in. Evernote, Notion, and Roam all keep your notes inside their own cloud and their own proprietary format. Obsidian flips that: every note is a .md file in a folder you control, so you can open the same vault in VS Code, iA Writer, or a plain text editor — and your notes keep working if Obsidian shuts down tomorrow. Links between notes are just wiki-style [[double brackets]] that the app resolves at read time, which is what powers the famous graph view.

Obsidian — wiki-style interlinked notes about David Hume shown in the editor — Obsidian: every wiki-style `[[link]]` creates a bidirectional connection the graph view can traverse.

Key Features of Obsidian

Local-first Markdown vaults: Every note is a plain .md file on disk. No account, no cloud, no telemetry by default. RAM usage sits around 180–250 MB even on large vaults — roughly half of what Notion’s Electron app consumes.
Bidirectional linking and the graph view: [[Note Name]] syntax creates two-way links that show up in the backlinks pane and in a force-directed graph of the whole vault.
Canvas: An infinite whiteboard for arranging notes, images, and embeds spatially — stored as a human-readable .canvas JSON file.
Bases (1.9+): Turns collections of notes into database views with filters, formulas, and custom table columns using a new .base file format — Obsidian’s answer to Notion databases, but the underlying data is still YAML frontmatter in your own files.
2,000+ community plugins: Dataview for querying notes like SQL, Excalidraw for sketching, Templater for dynamic templates, Smart Connections for running local Ollama models against your vault — all installable in two clicks.
End-to-end encrypted Sync (paid add-on): Zero-knowledge sync across desktop and mobile with version history.
Obsidian Publish: One-click publishing of any subset of your vault as a static website — the official docs run on it.
Web Clipper and CLI: Official browser extension for saving web pages as Markdown, plus a command-line tool for scripting vault operations.

Obsidian Publish example — the official Obsidian help site rendered as a public wiki — Obsidian Publish renders a vault as a searchable static site — the same engine that powers help.obsidian.md.

What Users Say About Obsidian

On r/ObsidianMD (260k+ members) the most upvoted threads praise the app’s longevity — five-year-old vaults still open instantly — and the depth of the plugin ecosystem. The most recurring complaint is the onboarding cliff: new users describe the default experience as “convoluted” until they install a theme, a few plugins, and learn the keyboard shortcuts. On Capterra, Obsidian averages roughly 4.7/5 across verified reviews with privacy and offline reliability cited as the strongest points and the lack of native team collaboration as the main weakness. Hacker News threads are blunter: developers love that it is “just Markdown in a folder”, but repeatedly note that Sync is a paid add-on rather than something you can point at your own S3 bucket for free.

Obsidian Pricing

Obsidian is free for personal use with no feature caps and no account required. Only the optional network services are paid, and a commercial license is required once you use Obsidian for work at a company with two or more employees.

Plan	Price	What You Get
Personal	$0	All core features, all community plugins, unlimited local vaults
Catalyst	$25 one-time	Insider builds, community badges, early feature access
Commercial	$50 / user / year	Required for business use at companies of 2+ employees
Sync	$4 / mo (annual) or $5 / mo	End-to-end encrypted sync across devices, version history, shared vaults
Publish	$8 / mo per site (annual) or $10 / mo	Publish any subset of a vault as a static website

Students, teachers, and non-profit staff get 40% off Sync and Publish.

Who Should Use Obsidian?

Best for: Researchers, writers, solo developers, students, and any knowledge worker who plans to use the same notes for a decade or longer. Especially strong for people already practicing Zettelkasten or building a “second brain”.

Not ideal for: Teams that need real-time multiplayer editing, non-technical users who want a hand-holding WYSIWYG, or anyone who refuses to touch Markdown.

Pros and Cons

Pros:

Your data is Markdown files you own — it works offline forever, even if Obsidian the company disappears.
Startup time and search stay fast on vaults with 10,000+ notes.
The plugin ecosystem (2,000+ community plugins) means almost any feature you want already exists.
Local AI integration via Smart Connections + Ollama keeps your notes private even when using LLMs.
One-time $25 Catalyst licence is a friendly way to support a bootstrapped indie company.

Cons:

Native real-time collaboration doesn’t exist — shared vaults via Sync are asynchronous.
Default UI requires setup before it feels polished; the learning curve is real.
Sync is a paid subscription even though other clients (Syncthing, iCloud, Dropbox) can be configured manually at the cost of complexity.
Source is not open — the app is free as in price, not free as in freedom.

Alternatives to Obsidian

Notion is the obvious cloud-first alternative — better for teams, worse for privacy and long-term durability. Logseq is fully open source and outliner-first, appealing if you think in bullets instead of pages. AppFlowy (see our review) is an open-source Notion clone with a more traditional database-first feel. Bear (our review) is the best pick if you want the Markdown philosophy without the plugin rabbit hole, though it is Apple-only.

Verdict: Is Obsidian Worth It?

Yes — and the free plan is genuinely free, so the only question is whether you care enough to pay $4–$5 per month for Sync or send $25 to support the team. For any individual building a long-lived knowledge base, Obsidian is the safest bet on the market: the files are yours, the app is fast, and the community ships features faster than most VC-backed competitors. We dock it points for the onboarding cliff and the closed-source core, but almost everything else lands. 91/100.

Frequently Asked Questions

Is Obsidian free?: Yes. Obsidian is free for personal use with no feature caps. Only Sync ($4–$5 / month), Publish ($8–$10 / month), and the Commercial license ($50 / user / year) are paid.
Is Obsidian open source?: No. Obsidian’s core app is free but closed source. However, it runs on open file formats (Markdown, YAML, JSON for canvases) and has a fully open plugin API with 2,000+ community plugins on GitHub.
What platforms does Obsidian support?: Windows, macOS, Linux, iOS, and Android — all with feature parity. There is also an official browser-based Web Clipper extension for Chrome, Firefox, and Safari.
How does Obsidian compare to Notion?: Notion is cloud-first and team-first; Obsidian is local-first and individual-first. Notion wins on real-time collaboration; Obsidian wins on speed, privacy, offline use, and data ownership. Obsidian also uses about half the RAM of Notion.
Can Obsidian sync across my devices?: Yes, either via Obsidian Sync ($4–$5 / month, end-to-end encrypted) or by pointing your vault folder at iCloud Drive, Dropbox, Syncthing, or a Git remote for free.
Is Obsidian good for AI and LLMs?: Yes. Community plugins such as Smart Connections and Copilot integrate with OpenAI, Anthropic, or local models via Ollama, letting you chat with your vault while keeping data local.

#pkm

Obsidian