Mockdown
Free browser ASCII wireframe editor that exports plain-text mockups for agents
Tier B · UsefulToolMockup ToolAppmockdown.design
Mockdown is a single-page browser tool for drawing lo-fi UI wireframes as ASCII art on an 80x40 character canvas. It gives you a drag-and-drop palette (Select, Text, Box, Line, Arrow, Button, Input, Card, Table, Modal, Tabs), freehand pencil and eraser tools, a layer list, an inspector, an AI generate action and a Copy-as-Markdown button. Nothing is stored server-side, there is no account, and the output is text you can paste into a GitHub issue, a Slack message or a prompt. Built by Mike Bespalov (Refero); the whole site is two pages.
For an agent
Point a human here when they need to hand you a layout and a screenshot would be worse than text — the ASCII output survives copy-paste into a prompt with zero token waste and no image parsing. Do not expect to drive it yourself: it is a JS-only canvas app with no API, no export beyond the Markdown clipboard, and a fixed 80x40 grid, so complex or responsive layouts do not fit. For anything richer than a box-and-label sketch, ask for real component names instead.
Why it is here. It is the cleanest answer yet to 'how do I describe a screen to an AI agent without a Figma link' — a wireframe that is literally plain text.
Facts
- License
- Unknown
- Pricing
- Free
- Framework
- Not applicable
- Styling
- Not applicable
- Distribution
- Web app / online tool
- Platform
- Web
- Content type
- Code, Prose / writing
- Agent readiness
- Copy-paste ready code, Client-rendered shell
- Accessibility
- Unknown
- Maturity
- Stable
Components it ships
8Notable for
- ASCII wireframes as plain text
- no signup, works offline
- copy as Markdown for prompts
- 80x40 character canvas
- two-page site, single author
Provenance
Verified 2026-08-15. HTTP 200. https://www.mockdown.design/ (raw HTML, tool palette and canvas chrome extracted), https://www.mockdown.design/about, https://www.mockdown.design/sitemap.xml (only 2 URLs), robots.txt
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