D2 is a concise scripting language that lets you generate diagrams directly from plain text. It focuses on simplicity and readability, making it easy to embed visualizations in documentation and codebases. Designed for self‑hosted environments, D2 runs in the browser and can be integrated into CI pipelines, providing free, on‑premise diagram generation without vendor lock‑in.
SmartDraw is a diagramming platform that lets users create flowcharts, org charts, floor plans, network diagrams, mind maps, and technical engineering drawings without CAD expertise, using automatic formatting and drag-and-drop symbol libraries. It ships with over 4,500 professionally designed templates covering more than 70 diagram types, each paired with an industry-relevant symbol library, from commercial floor plans to fire pre-plans and accident reconstructions. SmartDraw integrates with Microsoft Office and Google Workspace for one-click export and sharing, and supports both cloud and desktop access with enterprise features like SSO provisioning and dedicated support. It is used by a large share of Fortune 500 companies and is positioned as a more template-rich, automation-focused alternative to blank-canvas diagramming tools like Visio or draw.io.
- Zero cost, fully free
- Self‑hosted for full data control
- Simple, readable syntax reduces learning curve
- Integrates easily with CI pipelines and GitHub
- Massive template library reduces time spent building diagrams from scratch
- Automatic formatting keeps diagrams visually consistent with minimal effort
- Strong Microsoft and Google Workspace integration for easy sharing
- Used by a large majority of Fortune 500 companies
- Limited to 2D diagram types
- No native desktop application, relies on web UI or CLI
- Advanced styling requires manual configuration
- No free-forever tier, only a limited trial
- Per-user pricing can be costly for larger organizations
- Less flexible for fully custom, non-template diagram styles compared to blank-canvas tools
More alternatives & similar tools
Alternatives to d2
View all →Alternatives to SmartDraw
View all →Real-time collaborative diagramming for flowcharts, wireframes, and org charts by the makers of Backlog.
The Omni Group's Mac and iPad tool for professional diagrams, wireframes, and vector design.
The Verdict
AI-generated from listing datad2 is a free, open‑source, developer‑focused diagram tool with a simple markdown‑like syntax, while SmartDraw is a paid, template‑rich enterprise solution with strong Office integrations.
Key differences
- •Cost: d2 is free and self‑hosted; SmartDraw requires a subscription per user.
- •Template library: SmartDraw offers 4,500+ ready‑made templates; d2 provides no built‑in templates.
- •Integration focus: SmartDraw integrates natively with Microsoft Office and Google Workspace; d2 only offers API and GitHub Actions.
- •Deployment: d2 can be self‑hosted for full data control; SmartDraw is cloud‑based with optional desktop client.
- •Support model: d2 relies on email and GitHub Issues; SmartDraw provides dedicated support with enterprise plans.
Pricing & value
d2 is free and open source; SmartDraw only offers paid subscriptions.
Ease of use / learning curve
SmartDraw’s massive template library lets non‑technical users create diagrams quickly; d2 requires learning its syntax.
Features & depth
SmartDraw provides 4,500+ templates and automatic formatting; d2 supports only 2D diagrams and manual styling.
Integrations & ecosystem
SmartDraw integrates natively with Microsoft Office and Google Workspace; d2 only offers API, GitHub Actions, and CLI.
Collaboration
SmartDraw supports cloud and desktop sharing with enterprise SSO; d2 relies on self‑hosted web editor and Git workflows.
Scalability
d2 can be self‑hosted and scaled via own infrastructure; SmartDraw’s scalability depends on vendor’s SaaS limits.
Support & security
SmartDraw offers dedicated support and enterprise SSO; d2 provides only email and GitHub Issues, but is self‑hosted for data control.
Choose d2 if…
Developers or technical writers needing a free, scriptable, self‑hosted diagram solution.
Choose SmartDraw if…
Enterprises or business users who value extensive templates, Office integration, and dedicated support.
Common questions
Can I try SmartDraw for free?
SmartDraw offers only a limited trial; there is no free‑forever tier.
Does d2 support Windows desktop installation?
No native desktop app; d2 runs via web UI or command‑line interface.
Which tool allows me to keep diagram data on‑premises?
d2 can be self‑hosted, giving full control over data; SmartDraw is primarily cloud‑based.