ASCII mode turns your Mermaid diagram into text art — perfect for code comments, README files, pull request descriptions, terminal output, or anywhere an image can’t go.
Switching to ASCII mode
Click ASCII in the navbar’s mode switcher (or open /ascii directly). The same Mermaid code in the editor is rendered as characters instead of an SVG:
┌───────┐ ┌────────┐
│ Start │─────▶│ Ship it│
└───────┘ └────────┘ASCII rendering is powered by beautiful-mermaid, a TypeScript port of mermaid-ascii. The renderer is lazy-loaded, so it only downloads when you first open ASCII mode.
Settings
With ASCII mode active, the right panel shows the ASCII settings:
- Charset —
Unicode ─│┌uses box-drawing characters for smooth lines and corners;ASCII - | +restricts output to plain ASCII characters for maximum compatibility (old terminals, code review tools, plain-text email). - Font Size — scales the rendered text, useful for fitting a large diagram into a narrow comment block.
Supported diagram types
Flowcharts and sequence diagrams render best. Some Mermaid diagram types aren’t supported by the ASCII renderer yet — for those, the preview shows a localized fallback message instead of a broken render.
Very long links (---->) are normalized automatically before rendering, so diagrams with stretched edges still produce sensible output.
Exporting
In ASCII mode the Export dialog offers TXT (plain text) — the rendered text diagram, ready to paste anywhere. See Export & Share.
Browsing ASCII templates
Open /ascii/templates to browse the template gallery rendered as ASCII art. Unsupported templates are filtered out automatically, and the type filter chips help you find a starting point. See Templates.