Tour of the app
The whole story first: CRAYON-C4 has three diagram types, and each gets two screens — a viewer for reading and a matching editor for changing things. A hamburger menu in the top-left corner of every screen jumps between all of them. Your work saves itself in your browser as you go, and a built-in demo project lets you explore a fully worked example before you draw anything yourself.
The screens
| Screen | What you do there |
|---|---|
| C4 viewer | Read structure diagrams, click elements for details, drill into deeper levels |
| C4 editor | Add and arrange elements, connect them, manage levels |
| Deployment viewer | Read "what runs where" per environment |
| Deployment editor | Build environments, place infrastructure and running instances |
| Flow (F4) viewer | Read process flows lane by lane |
| Flow (F4) editor | Build lanes, activities, and connections |
Take the tour
If you prefer a guided walkthrough, launch the product tour from the navigation menu (top-left hamburger) → Take the tour. It starts at the projects hub, first shows how the hamburger menu reaches every viewer and editor, then visits each of the six screens in turn — opening the menus and dialogs it talks about so you see the real thing. It takes a few minutes, and every step tells you how to get back to what it shows. You can also find "Show me how" buttons in any empty-state view if you get stuck.
The three-pane editors
Every editor uses the same three-pane layout: a tree of everything in the diagram on the left, the canvas in the middle, and a details form for the selected item on the right.
The demo project
The fastest way to learn is to look at a finished example. The demo project contains a small but complete model — structure, deployment, and flows — that all the guide pages in these docs use for their screenshots.
To load it: go to Projects, click New project, then choose Demo project from the source picker. The demo is created as a new project of its own — whatever you were working on stays untouched.
Where your work lives
Everything you draw is saved automatically in your browser — no account, no save button. That storage belongs to this browser on this machine: a different browser or computer starts empty.
When you need more, you can sign in:
- a free account adds JSON export/import, so your work can be backed up and moved;
- the Pro version saves projects to the cloud, syncs across machines, and adds team features.
The Projects & sharing section covers all of this.
Where next
- Your first diagram — build something in ten minutes.
- The three views of a system — which diagram answers which question.