ASCII Diagrams

Note: ASCII Diagrams are a PRO feature.

ASCII Diagrams let you create text-based diagrams using ASCII and Unicode characters. These diagrams can be exported as plain text, making them perfect for code comments, README files, terminal output, and documentation where images aren't practical.

Creating an ASCII Diagram

  1. Click the + button in the tab bar
  2. Select ASCII Diagram (marked with a lock icon in the free version)
  3. A new tab opens with a character grid canvas

The ASCII canvas works differently from the standard freeform canvas — you draw with characters on a fixed grid rather than placing vector shapes.

Drawing Tools

On an ASCII page the toolbar changes to ASCII tools:

  • Draw menu:
    • Shapes — Box, Ellipse, and Rounded Box
    • Lines — Line and Arrow
  • Text Tool (T) — type text directly onto the grid
  • Unicode / ASCII toggle — switch the character set used on the canvas

Character Sets

Diagrammix supports two character sets for ASCII diagrams:

ASCII

Uses standard ASCII characters available on any system:

+---+     +---+
|   |---->|   |
+---+     +---+

Unicode

Uses Unicode box-drawing characters for cleaner lines:

┌───┐     ┌───┐
│   │────>│   │
└───┘     └───┘

Exporting

Export your ASCII diagram as a plain text file:

  1. Go to File → Export as ASCII Text...
  2. In ASCII Text Export Options, choose the Character Set — Auto (no conversion), Unicode (box-drawing), or ASCII (plain)
  3. Set Max Columns to limit the line width
  4. Click Export and choose a save location

Export as ASCII Text... also works on regular (freeform) pages — the diagram is converted to text.

The exported .txt file contains your diagram as pure text, ready to paste into code, documentation, or chat.

Use Cases

  • Code documentation — Add diagrams to source code comments
  • README files — Include architecture diagrams in Markdown docs
  • Chat and email — Share diagrams where images aren't supported
  • Terminal tools — Display diagrams in command-line applications
  • Plain text notes — Keep diagrams in simple text files

Tips

  1. Use Unicode for cleaner-looking diagrams when your target supports it
  2. Use ASCII for maximum compatibility (works everywhere)