Gitdiagram
Free, simple, fast interactive diagrams for any GitHub repository
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What is Gitdiagram?
GitDiagram is a free, AI-powered tool that instantly converts any GitHub repository into an interactive system architecture diagram for quick codebase understanding. It uses OpenAI o4-mini (previously Claude 3.5 Sonnet) to analyze the file tree and README, then generates Mermaid.js diagrams that visualize the entire project structure in seconds.
Key features include instant visualization of repository structure, interactivity where you can click on diagram components to navigate directly to source files and directories, fast generation powered by AI, customization options to modify and regenerate diagrams with custom instructions, and a simple URL trick where you replace 'hub' with 'diagram' in any GitHub URL to access its diagram. The tool also supports private repositories through GitHub personal access tokens and offers public API access for integration (currently WIP).
GitDiagram is built with a modern tech stack including Next.js, TypeScript, Tailwind CSS, FastAPI, Python, PostgreSQL with Drizzle ORM, and is deployed on Vercel (frontend) and EC2 (backend). It is open-source under the MIT license with 14.6k stars on GitHub.
The tool is ideal for developers who want to contribute to open-source projects but find codebases too massive to navigate manually, students learning new codebases, project maintainers documenting their systems, teams collaborating on code understanding, and anyone who needs to quickly understand project architecture without digging through files.
GitDiagram extracts information from the file tree and README for details and interactivity, using prompt engineering to extract and pipeline data for the diagram generation workflow.
Gitdiagram pricing
Pricing model: Freemium
Free - GitDiagram is currently hosted for free with no rate limits, though the creator notes this is somewhat likely to change in the future. The tool is open-source under MIT license, and users can also self-host it locally for free. No paid plans are currently offered.
Gitdiagram pros
- 100% free with no rate limits currently
- Open-source under MIT license
- Instant visualization in seconds
- Click components to navigate to source files
- Works with public and private repositories
- Simple URL replacement trick (hub to diagram)
- Customizable diagrams with custom instructions
- Generates Mermaid.js output
- Download diagrams as PNG or Mermaid files
- No setup required - works instantly
- Public API available for integration
- Self-hosting option available
- Fast generation powered by OpenAI o4-mini
- Extracts info from file tree and README
- 14.6k GitHub stars proving reliability
Gitdiagram cons
- Currently only supports GitHub repositories
- Private repos require manual GitHub token setup
- Public API still work-in-progress
- May change free pricing in the future
- No built-in version history tracking yet
- Diagram quality depends on README quality
- No support for other Git platforms (GitLab, Bitbucket)
- Requires internet connection - not offline-capable
- Limited icon support (font-awesome icons planned)
- No progressive diagram updates on commits yet
Frequently asked questions about Gitdiagram
What is GitDiagram?
GitDiagram is a free, AI-powered tool that turns any GitHub repository into an interactive system architecture / design diagram for visualization in seconds. It uses OpenAI o4-mini to analyze the repository's file tree and README, then generates Mermaid.js diagrams.
How do I use GitDiagram?
You can use GitDiagram in two ways: (1) Enter a GitHub repository URL on gitdiagram.com and click 'diagram', or (2) Simply replace 'hub' with 'diagram' in any GitHub URL (e.g., github.com/user/repo becomes gitdiagram.com/user/repo) and hit enter.
Is GitDiagram free?
Yes, GitDiagram is currently 100% free with no rate limits. The creator is hosting it for free but notes this is somewhat likely to change in the future. It's also open-source under MIT license so you can self-host it.
Can I visualize private repositories?
Yes, you can diagram private repositories by clicking 'Private Repos' in the header and providing a GitHub personal access token with the 'repo' scope.
What AI model powers GitDiagram?
GitDiagram uses OpenAI o4-mini for generating diagrams (previously used Claude 3.5 Sonnet). The AI extracts information from the file tree and README to create accurate system architecture diagrams.
What format are the diagrams in?
GitDiagram generates diagrams in Mermaid.js format. You can also download diagrams as PNG files or Mermaid files for further use.
Can I customize the diagrams?
Yes, GitDiagram allows you to modify and regenerate diagrams with custom instructions to get the visualization that best fits your needs.
Is GitDiagram open-source?
Yes, GitDiagram is 100% open-source under the MIT license. The GitHub repository has 14.6k stars and you can self-host it locally with the provided setup instructions.
Can I integrate GitDiagram into my own tools?
A public API is available for integration but is currently work-in-progress (WIP). You can check the GitHub repo for updates on API availability.
How do I self-host GitDiagram?
Clone the repository, install dependencies with pnpm i, set up environment variables (.env file with your API key), run backend with docker-compose, start the PostgreSQL database, initialize with pnpm db:push, and run frontend with pnpm dev. Full instructions are in the GitHub README.