ASCII Canvas Editor: a free ASCII diagram maker

ASCII Canvas Editor is a free, browser-based tool for drawing diagrams and art out of text characters. Sketch flowcharts, architecture diagrams, wireframes and README graphics, then copy them as plain text or download them as a PNG. It runs entirely in your browser with nothing to install.

How to use it

1. Choose a tool from the toolbar, or press its key: R rectangle, D diamond, L line, A arrow, T text, F freehand, E eraser.
2. Click and drag on the canvas to draw. Pick a border, line or arrowhead style in the left panel.
3. Use V to select and move shapes, and Ctrl+Z to undo.
4. Press Copy ASCII to copy the text, or Download PNG to save an image.

Features

• Rectangles with Simple, Double, Rounded, Heavy and Light borders
• Diamonds, lines and arrows in ASCII, light, heavy, dashed and dotted styles
• Text, freehand drawing with selectable characters, and an adjustable eraser
• Undo and redo, zoom and pan, keyboard shortcuts for every tool
• Dark and light themes, PNG export and one-click copy

Frequently asked questions

How do I make an ASCII box diagram?

Pick the Rectangle tool (R), choose a border style such as Simple, Double, Rounded, Heavy or Light, then click and drag on the canvas. Add Arrow and Line tools to connect boxes and the Text tool to label them.

Can I export my ASCII art as an image?

Yes. Download PNG saves your drawing as a sharp image that matches the current dark or light theme. Copy ASCII puts the plain text on your clipboard so you can paste it into code comments, READMEs or documentation.

Does it support Unicode box-drawing characters?

Yes. Rectangles, lines and diamonds can use Unicode box-drawing characters like ┌─┐, ╔═╗ and ╭─╮ as well as plain ASCII characters such as + - and |. The editor ships with JetBrains Mono so every character lines up on the grid.

Is the ASCII Canvas Editor free?

Yes, it is free and open source. Everything runs in your browser; your drawing is never uploaded anywhere.

Can I move or erase parts of a drawing?

Use the Select tool (V) to drag any connected shape to a new position, or drag a box around an area and press Delete. The Eraser tool (E) removes characters under the cursor, and Ctrl+Z undoes any change.

How do I zoom and pan?

Scroll to zoom toward the cursor. Hold Space and drag, or drag with the middle mouse button, to pan around the 200 × 80 character canvas.