free · local-first · no signup

Text in. Diagrams out.

FlowViz turns plain Mermaid syntax into crisp SVG diagrams as you type — right in your browser, with no account and nothing to install.

Learn the syntax
Live · editablediagram.mmd
Edit the code — the diagram follows
21diagram types
0accounts required
Freeno paywall
Livepreview as you type

Two-way editing

Click a shape. Edit it. The code updates itself.

A Mermaid editor is usually a one-way street: you type, it draws. FlowViz goes both ways, with no account to create first. Select a node on the canvas and change its shape, colour or label — the Mermaid source rewrites itself, and one undo takes back the whole edit. Your file stays the source of truth; nothing is generated behind your back.

Available for flowcharts today. Every other diagram type renders and exports exactly as before.

Why FlowViz

A diagram tool with nothing between you and the diagram.

Local by default

Diagrams live in your browser’s localStorage — no account, no cloud sync. Nothing is uploaded unless you create a short link on purpose.

localStorage by default

Renders as you type

No render button, no refresh. The canvas redraws the moment you pause, so the diagram is always the current draft.

no render button

Clean SVG out

Export a crisp, infinitely scalable vector file. Drop it straight into docs, slides, Figma, or a README.

.svg export

Powered by Mermaid v11

21 diagram types, ready to write.

FlowchartSequenceClassStateEntity RelationshipGanttGit GraphPie ChartMindmapTimelineQuadrantSankeyXY ChartBlockArchitectureUser JourneyRequirementC4KanbanRadarPacket

The linked types have dedicated maker pages with worked examples and syntax basics — or start from a blank canvas in the editor.

How it works

Type it. Click it. Export it.

flowviz.app — untitled.mmd

Type it

flowchart TD · A[Start] --> B{Deploy?} — the canvas redraws as you type. No run button, no signup, no install.

Click it

Select a box and change its shape, colour or label — the Mermaid source rewrites itself. Flowcharts today.

Export it

SVG or PNG at any size, or copy a link that carries the whole diagram with it.

FAQ

Common questions, answered.

Is FlowViz free?

Yes — FlowViz is completely free, with no account, no paywall, and no usage limits. Every diagram type and every export option is available on the first visit.

Do my diagrams get uploaded anywhere?

By default, no — diagrams render and stay entirely in your browser’s local storage. The only exception is the optional short-link feature, which stores that one diagram on the server so the link keeps working for others.

What diagram types does FlowViz support?

All of Mermaid’s diagram types, including flowcharts, sequence diagrams, Gantt charts, ER diagrams, class diagrams, state diagrams, pie charts, git graphs, mindmaps, and timelines.

Do I need to know Mermaid syntax to use FlowViz?

No prior experience is required — the built-in template picker and cheatsheet cover the syntax for every diagram type, and every maker page ships with a working example you can edit directly.

Your next diagram is one tab away.

No signup. No install. Nothing to configure.