State diagram maker

State Machine Diagram Generator — type transitions, get a clean FSM

Make a state diagram online by typing plain text. Each line is a transition — from-state, arrow, to-state, event label — and the finite state machine renders live with a presentation-ready layout. Free, no signup, exports to SVG and PNG.

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What is a state diagram?

A state diagram (or state machine diagram) shows every state a thing can be in and the events that move it between them: an order from placed to shipped, a document from draft to published, a connection from idle to closed. Start and end markers bracket the lifecycle, and each labelled arrow is a transition — which makes missing transitions and unreachable states visible at a glance.

Common use cases

Workflow and approval lifecycles

Draft → review → approved → published, with rejection loops — exactly the shape of document, ticket, and order lifecycles.

Protocol and connection states

Connecting, retrying, backing off, closed — a state diagram is the honest picture of what your client actually does under failure.

UI and feature states

Loading, empty, populated, error — enumerate the screens a component can be in and the events that move it, before the edge cases surprise you.

Syntax quick reference

The essentials to get productive — paste any of these into the editor above and adapt. For the full grammar, see the state diagram syntax reference.

SyntaxWhat it does
stateDiagram-v2Start a state diagram.
[*] --> DraftThe start marker — the initial state.
Draft --> InReview : submitA transition with its triggering event after the colon.
Published --> [*]A transition to the end marker.
state Fork <<fork>>Fork/join bars for parallel paths.
state Active { … }A composite state with nested substates.

Export options

SVG

Vector output with fonts inlined — crisp at any zoom, right for docs, READMEs, and the web.

PNG

Raster with optional transparent background and up to 4× scale — right for slides and tickets.

Share link

One click publishes a share page with the beautified diagram — no file juggling for reviews.

Frequently asked questions

How do I make a state diagram online for free?

Type one transition per line in the editor above — FromState --> ToState : event. The finite state machine renders live with a clean layout and exports to SVG or PNG without signup.

How do I show where the state machine starts and ends?

Use the [*] marker: [*] --> Draft is the entry point, Published --> [*] is a terminal transition. A machine can have multiple terminal transitions — every path that legitimately ends should reach [*].

Can I model loops, like a rejection that goes back to review?

Yes — a transition back to an earlier state is just another line: ChangesRequested --> InReview : resubmit. The preloaded example has a full reject/resubmit loop; edit it in place to watch it re-render.

What is the difference between a state diagram and a flowchart?

A flowchart follows one execution through steps and decisions; a state diagram describes all the states a single thing can occupy and the events that move it. If your boxes are verbs, you want a flowchart; if they are conditions of being — Draft, Approved, Closed — you want a state machine.

Can I generate the diagram from AI output?

Yes. Ask any AI assistant for "a Mermaid stateDiagram-v2 of …", paste the code here, and it renders with a beautified layout. A command-line tool and editor plugins let agents and scripts export diagrams directly.

Is this state diagram maker really free?

Yes. Anonymous use covers live preview, beautify, and SVG/PNG export with a small watermark; a free account removes the watermark. Per-month export quotas are listed on the pricing page.

Ready to make your own?

Open the full editor to save your work, switch themes, and export clean SVG or PNG. No signup.