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D2

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What D2 is

D2 is a free, open-source declarative diagramming language that turns text into diagrams. It supports software architecture, UML class and sequence diagrams, with themes, sketch mode, animations, LaTeX, code snippets, Markdown and tables. Three layout engines are available, alongside specialized layouts for sequence diagrams and grids. The CLI exports D2 files, SVG, PNG, PDF, PPTX, GIF and ASCII. A hosted Playground provides an online place to learn and create diagrams, while the local CLI supports offline work after installation apart from periodic GitHub version checks. D2 can also be used as a Go library. Official integrations include VSCode, Vim and Obsidian, with additional community plugins. It runs on Linux, macOS and Windows and is available through API, web and self-hosted options. D2 is licensed under the Mozilla Public License 2.0. It is not designed for big data, and maintainers do not test diagrams with thousands of nodes.

Who it suits

D2 suits developers and technical teams who prefer text-defined diagrams, offline CLI workflows or editor integrations. It is also useful for users needing open-source exports and programmable diagram generation.

What it does well

  • Free and open source
  • Offline CLI workflow after installation
  • Exports SVG, PNG, PDF, PPTX, GIF and ASCII
  • Three layout engines
  • VSCode, Vim and Obsidian integrations

What to know first

  • Not designed for big data
  • Maintainers do not test thousands-node diagrams
  • CLI periodically checks GitHub for updates
  • Development time is limited

Verdict

D2 offers text-based diagram creation with broad export, layout and editor options at no cost. Its documented scale limitation matters for very large diagrams.

Facts from D2's own pages

Diagram features
D2 supports themes, sketch mode, animations, LaTeX, Markdown, code snippets, tables, containers, imports, variables, and interactive links and tooltips. · d2lang.com, 5 Oct 2026
Diagram types
software architecture diagrams; UML class diagrams; sequence diagrams · d2lang.com, 20 Sept 2026
Editor integrations
The homepage lists official VSCode and Vim editor support, and the repository lists official VSCode, Vim, and Obsidian plugins. · github.com, 4 Oct 2026
Export formats
The CLI exports diagrams to SVG, PNG, PDF, PPTX, GIF, and ASCII. · d2lang.com, 5 Oct 2026
Exports
D2 supports exports to SVG, PNG, PDF, PPTX, GIF, and ASCII. · d2lang.com, 4 Oct 2026
Free plan
Yes · d2lang.com, 20 Sept 2026
Funding
Donations support the project's public tools and infrastructure, and the project says donations do not affect its roadmap, governance, or license. · d2lang.com, 5 Oct 2026
Help and support
The repository recommends Discord for help, GitHub Issues for feature requests, proposals, or bug reports, and email for private inquiries. · github.com, 4 Oct 2026
Import/export formats
D2 (.d2); SVG; PNG; PDF; PPTX; GIF; ASCII · d2lang.com, 20 Sept 2026
Integrations
Official integrations include extensions for VSCode, Vim, and Obsidian; the extensions page also lists community plugins and tools. · d2lang.com, 5 Oct 2026
Layout engines
The Playground offers Dagre, ELK, and TALA layout engines. · play.d2lang.com, 5 Oct 2026
Layouts
D2 offers three layout engines and also handles specialized layouts such as sequence diagrams and grids. · github.com, 4 Oct 2026
License
The repository says D2 is open sourced under the Mozilla Public License 2.0. · github.com, 4 Oct 2026
Offline and telemetry
The CLI does not use an internet connection after installation except to periodically check GitHub for version updates. · d2lang.com, 5 Oct 2026
Offline editing
Yes · d2lang.com, 20 Sept 2026
Offline use
The homepage describes the local CLI as an offline workflow; the FAQ says D2 does not use an internet connection after installation except to check for version updates from GitHub periodically. · github.com, 4 Oct 2026
Online playground
The hosted Playground is an online runner for playing, learning, and creating with D2. · play.d2lang.com, 4 Oct 2026
Open source
D2 is free and open source, and remains under the Mozilla Public License 2.0. · d2lang.com, 5 Oct 2026
Other integrations
The repository lists community plugins and integrations including Emacs, Telegram, Postgres import, Confluence, and MkDocs. · github.com, 4 Oct 2026
Platforms
The CLI supports macOS, Linux, and Windows, and D2 can also run in a browser through WebAssembly. · d2lang.com, 5 Oct 2026
Privacy
The repository FAQ says D2 does not use an internet connection after installation except to check periodically for version updates from GitHub. · github.com, 4 Oct 2026
Programming API
D2 can be used as a library to produce diagrams from Go programs. · github.com, 4 Oct 2026
Project sponsorship
D2 is an independent open-source project fiscally sponsored by Hack Club. · d2lang.com, 4 Oct 2026
Project status
D2 is an independent nonprofit project fiscally sponsored by Hack Club, and its maintainer says development time is limited. · d2lang.com, 5 Oct 2026

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