Mermaid Diagram Editor
Render Mermaid diagram syntax into a live SVG preview as you type — flowcharts, sequence diagrams, class diagrams, state diagrams, entity-relationship diagrams, pie charts, and more, using the real Mermaid library (the same one behind GitHub, GitLab, and Notion diagrams). Diagram type is auto-detected, and a syntax error surfaces the actual parser message and line number. Download as SVG or PNG. Runs entirely client-side — nothing is uploaded.
Rendering…
About this tool
This tool renders Mermaid diagram syntax into a live SVG preview as you type — flowcharts, sequence diagrams, class diagrams, state diagrams, entity-relationship diagrams, and pie charts. Mermaid's diagram type is auto-detected from your code's first line (graph/flowchart, sequenceDiagram, classDiagram, and so on) and shown once it renders successfully. Rendering uses the real Mermaid library — the same one powering diagrams in GitHub, GitLab, and Notion — so a syntax error surfaces the parser's actual message and line number rather than a generic failure. It runs entirely client-side — nothing you type is ever sent anywhere, and diagram content is sanitized before being injected into the page.
What you can do
- Flowcharts, sequence, class, state, and ER diagrams, plus pie charts
- Live preview as you type — no separate render step
- Download as SVG or PNG
- Nothing is uploaded — diagrams render locally in your browser
How to use
Step 1
Start from a template or write your own
Click a preset to load a working example of that diagram type, then edit it.
Step 2
Watch it render live
The preview updates automatically as you type, with the exact Mermaid parser error if the syntax is invalid.
Step 3
Download the result
Export as a scalable SVG or a PNG.
Example
This code:
Mermaid
graph TD
A[User] --> B[Tuliq]
B --> C[Tool]renders as a simple top-down flowchart with three connected boxes — edit any part of it and the preview updates live.
How your data is handled
This tool is labeled 🟢 Browser: your diagram code is parsed and rendered directly in your browser using the Mermaid library — nothing is uploaded to a server, and nothing about it is retained once you leave the page.
Frequently asked questions
What diagram types are supported?+
Flowcharts, sequence diagrams, class diagrams, state diagrams, entity-relationship diagrams, and pie charts are covered by the starter templates — Mermaid itself supports several more (Gantt charts, user journeys, git graphs, mind maps), which this tool will also render since it uses the full library, even without a dedicated preset.
How is the diagram type decided?+
Mermaid detects it from the first line of your code — graph or flowchart for a flowchart, sequenceDiagram for a sequence diagram, and so on. It's shown under the code editor once your diagram renders successfully.
Why does it say my diagram has a syntax error?+
The error message comes directly from Mermaid's own parser, including the line it got stuck on — usually a missing arrow, an unclosed bracket, or a keyword that doesn't belong in that diagram type.
Can I download the diagram?+
Yes — as an SVG (scalable, edits cleanly in vector tools) or a PNG (a fixed-resolution raster image), both available once the diagram renders without errors.
Is my diagram code uploaded anywhere?+
No — it's parsed and rendered directly in your browser using the Mermaid library. Nothing here ever leaves your device.