Foam

Overview

Foam is a free, open-source personal knowledge management (PKM) tool based on VS Code, initiated by the community around 2019 and hosted on GitHub (foambubble/foam) under the MIT license. It borrows Roam Research's bidirectional linking idea, letting users build visualizable knowledge graphs from plain Markdown files and [[wikilink]] links, with all data stored locally and independent of any cloud service.

Foam's core philosophy is "local-first, open formats": notes are ordinary Markdown files, naturally managed with Git for version control and cross-device sync, and combinable with VS Code's rich extension ecosystem. As an open-source note representative in the productivity space, Foam is maintained and iterated by an active international community and suits technical users familiar with VS Code and Git who want to build a second brain.

Key Strengths

• Completely free and open source: MIT license with no limits on users, notes, or features; source code can be inspected, customized, and self-hosted long-term.
• Bidirectional links and knowledge graph: [[wikilink]] links combined with Graph View visualization reveal the relationship network between notes, ideal for building a personal knowledge base.
• Local data with zero lock-in: Notes are plain Markdown stored entirely locally, manageable with Git for versioning, migration, and backup with no platform lock-in risk.
• VS Code ecosystem leverage: Built on VS Code's editing power and extension ecosystem, freely combining templates, daily notes, tags, and code snippets.
• Very low resource footprint: No extra client needed; runs inside VS Code, a lightweight option for developers' daily use.

Product Ecosystem

Wikilinks & Graph View

The [[note]] syntax creates bidirectional links, Graph View visualizes note relationships, and the Backlinks panel shows incoming references.

Local Markdown Notes

Notes are plain Markdown files supporting tags, templates, code blocks, and attachment references, with fully local data.

Daily Notes & Templates

Built-in Daily Notes and template features support custom naming rules and default content.

Navigation & Exploration

Navigation suggestions, recent notes, and outline views help locate and discover related content quickly.

Community Extension Ecosystem

Through the VS Code marketplace, combine Git, Todo, charts, AI, and other extensions to customize personal workflows.

Limitations

• Desktop VS Code only: No official mobile or standalone app, so notes cannot be used directly on phones or tablets.
• Sync must be self-hosted: No built-in cloud sync; cross-device use requires configuring a Git repository or cloud drive, a high bar for non-technical users.
• Basic feature positioning: Lacks block references, database views, and publishing; advanced capabilities must be assembled from extensions.
• Community-driven support: Graphs and plugins depend on community maintenance, with weaker official support and documentation cadence than commercial note products.

Use Cases

• Technical users and developers (★★★★★): Familiar with VS Code and Git, free to customize workflows and build a personal knowledge base.
• Local-first and privacy-sensitive users (★★★★★): Data is fully local with no cloud storage, suited to users with data sovereignty requirements.
• Roam-style note enthusiasts （★★★★☆）: Bidirectional links and graph visualization offer a zero-cost Roam-like note experience.
• Multi-device mobile work （★★☆☆☆）: No official mobile app and self-hosted sync; compare Obsidian and similar options.

Pricing

Note: Foam is completely free with no paid features; for cross-device sync, a free GitHub repository is enough for basic needs.

FAQ

• Is Foam completely free? Yes. Foam is open source under the MIT license with no paid features; after installing VS Code, all features are free to use. See the productivity category for more free productivity tools.

• Foam vs Obsidian, which to choose? Both are based on local Markdown and bidirectional links. Foam is free and deeply integrated with the VS Code ecosystem, suiting developers; Obsidian offers official mobile apps and a more mature plugin marketplace. See productivity tool comparison.

• Does Foam support mobile? There is currently no official mobile app, so recording on a phone is inconvenient; you can sync with Git on the desktop and view notes with any Markdown editor on mobile. For an official mobile experience, consider Obsidian.

• Can Foam data be lost? Data consists of local Markdown files; as long as local files are kept, they can be restored, and a Git repository further guarantees versioning and backup safety. See enterprise knowledge base setup for local knowledge base practices.

• Is Foam suitable for beginners? It requires some VS Code and Git foundation; non-technical users may prefer out-of-the-box tools such as Obsidian.