DiagramGPT alternative · 2026
DiagramGPT shows what AI diagramming can do. Datadef makes it a working tool: an editable canvas with data-native nodes, real vendor icons, lineage, exports, and embeds, free to try, right here.
Try the difference right now
Generate the kind of diagram you'd build in DiagramGPT: free, in your browser, no account.
No account needed · Editable canvas, not a picture
DiagramGPT is Eraser’s free demo. The moment you want to seriously edit or keep working, you are in Eraser’s plans, where AI calls are metered by monthly credits that reset. Datadef’s free scratch canvas is the actual product, the same canvas and the same AI an account gets.
DiagramGPT produces flowcharts, ERDs, and cloud sketches with generic shapes. Datadef outputs typed nodes (tables with columns, pipelines, sources, KPIs) plus 2,000+ vendor icons, so the result is presentable in a design review without rework.
In Datadef you keep going: refine with AI chat, version and publish, export PNG or JPEG, embed a live-rendering image in Notion, Confluence, or a README, and let AI agents update the diagram over MCP.
| Feature | Datadef | DiagramGPT |
|---|---|---|
| Free AI generation, no account | ||
| Editable after generation | Full visual canvas | Via Eraser plans |
| Data-native nodes & column lineage | ||
| Vendor icons (AWS, Azure, GCP, dbt…) | 2,000+ | Generic shapes |
| Export PNG / JPEG, live embeds | Limited | |
| Native MCP server for AI agents | ||
| Path to a real workspace | From $8/mo, unlimited AI | Eraser seats + credits |
Want the full head-to-head? Datadef vs Eraser (DiagramGPT’s home) →
The standalone DiagramGPT page is free to use: it exists to introduce Eraser. Once you edit seriously inside Eraser, AI usage is metered by your plan’s monthly credits. Datadef’s scratch canvas is also free, 1 AI diagram and 2 AI edits a day, and Pro is a flat $12 a month with unlimited AI under fair use.
The scratch canvas is free every day with no account: 1 AI diagram and 2 AI edits a day, unlimited manual editing and PNG, JPEG and JSON export, in your browser. Pro adds unlimited AI under fair use, cloud projects, repo sync, live embeds, sharing and MCP, after a 7-day free trial.
Datadef focuses on data and cloud architecture: platforms, pipelines, warehouses, lineage, microservices. For pure UML or sequence diagrams, a code-based tool like Mermaid or Eraser is the better fit: that honesty cuts both ways.
Claude Code, Claude Desktop, Cursor, VS Code, Codex, and Gemini CLI can drive Datadef through its native MCP server, create, edit, and export diagrams from a conversation, with the PNG returned inline.
Free scratch canvas, no account, no credit card: 1 AI diagram and 2 AI edits a day. Pro unlocks unlimited AI, saved projects, repo sync, live embeds and MCP for $12 a month or $96 a year, after a 7-day free trial.
Open the free canvas