Pencil

Mac

Free Open-Source Prototyping for UI/UX and Diagrams

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Overview

Pencil is a free, open-source tool for creating UI/UX wireframes, prototypes, mind maps, and flowcharts on Mac. Ideal for designers, developers, and product teams, it offers a drag-and-drop interface with pre-built elements (buttons, forms, icons) to speed up creation. Export prototypes to PDF, PNG, SVG, or HTML for sharing. Lightweight and easy to use, it lacks some advanced features of premium tools but excels at quick, no-cost prototyping and diagramming tasks.

Key Features

  • Drag-and-drop UI/UX prototyping elements
  • Open-source and free to use
  • Supports mind maps, flowcharts, and wireframes
  • Export to PDF, PNG, SVG, and HTML
  • Mac-compatible (cross-platform support)

Top Alternatives

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Tool Info

Pricing Free
Category Prototyping and Mind-Mapping Tools
Platform Mac

Pros

  • ⊕ Completely free and open-source
  • ⊕ Simple drag-and-drop interface
  • ⊕ Versatile for multiple diagram types
  • ⊕ Lightweight performance on Mac

Cons

  • ⊖ Outdated user interface
  • ⊖ Limited interactive prototyping features
  • ⊖ Fewer pre-built templates than premium tools

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