Diagrams.so vs Mermaid Chart
Diagrams.so
diagrams.soMermaid Chart
mermaid.aiSide by side
| Figure | Diagrams.so | Mermaid Chart |
|---|---|---|
| Price from | $10/mo | $12/mo |
| Free plan | Yes | Yes |
| Free trial | — | Yes |
| Open source | — | — |
| Web | Yes | Yes |
| API | Yes | Yes |
| Plans published | 3 | 4 |
| Spec score · AI Diagram Generators | 8.2 (#11) | 7.9 (#17) |
| Diagram types | It generates flowcharts, sequence diagrams, ERDs and cloud infrastructure diagrams. | Supported diagram types include flowcharts, sequence diagrams, Gantt charts, ER diagrams, timelines, mind maps, org charts, state diagrams, class diagrams, pie charts, and quadrant charts. |
| Integrations | The product offers a REST API, MCP server, and Python and TypeScript SDKs, and names Claude, Cursor and VS Code as MCP clients. | Official plugins and add-ons cover VS Code, JetBrains IDEs, Cursor, Windsurf, Claude Code, ChatGPT, Confluence, Jira, Google Docs, Microsoft Word, and PowerPoint. |
| Security | The maker says data is encrypted in transit with TLS 1.3 and at rest with AES-256, and that it does not train AI models on customer diagrams or prompts. | Mermaid states that it provides secure access controls, encryption, SOC 2 compliance, and SSO. |
| Support | The Power plan includes priority support, and the About page lists [email protected] for questions, feedback and partnership inquiries. | Enterprise is described as including custom contracts, support, and additional services. |
Plans
Mermaid Chart
- BasicFree
- Plus$12 a month
- Premium$24 a month
- EnterprisePriced on request
In their own words
Diagrams.so
Diagrams.so turns written descriptions into editable architecture diagrams, saved in Draw.io format. It generates flowcharts, sequence diagrams, entity relationship diagrams and cloud infrastructure diagrams, with official AWS, Azure, Google Cloud Platform and Kubernetes icon libraries alongside network, database, security and general-purpose shapes. Opinionated Mode can suggest missing components; non-blocking warnings flag risks such as single-AZ deployments and publicly exposed resources. Diagrams export as.drawio XML, PNG or SVG, and.drawio files open in Draw.io, Confluence, VS Code and Notion. Users can import.drawio files on every plan and compare or restore versions using history. The product offers a REST API, MCP server, and Python and TypeScript SDKs, with Claude, Cursor and VS Code listed as MCP clients. Free includes five credits, requires a BYO LLM key and watermarks exports. Free-tier diagrams are public; private diagrams require Pro or Power. Pro costs $10 a year billed annually or $15/mo billed monthly; Power costs $16.67 a year billed annually or $25/mo billed monthly.
Mermaid Chart
Mermaid Chart turns plain-text Mermaid syntax into diagrams and refreshes the visual when the text changes. Mermaid AI can also create diagrams from natural-language prompts or uploaded PDF, Word and plain-text files. Supported types include flowcharts, sequence diagrams, Gantt charts, ER diagrams, timelines, mind maps, org charts, state and class diagrams, pie charts and quadrant charts. Teams can co-edit in real time, comment and share live links. Official plugins and add-ons connect it with development environments, AI assistants, documentation tools and office products, including VS Code, JetBrains IDEs, Cursor, Windsurf, Claude Code, ChatGPT, Confluence, Jira, Google Docs, Word and PowerPoint. Mermaid AI exports PNG and SVG files. Mermaid MCP can validate and render diagrams without authentication; authenticated users can use it to manage diagrams and projects. Basic costs nothing and includes three diagrams and 15 AI credits. Plus costs $12 a month billed annually; Premium costs $24 a month billed annually. Trial and paid-tier content is not used to train Mermaid AI models; Basic-tier content may be used to improve services.