Pencil Project review
A free desktop tool for wireframes, mockups, flowcharts, and basic diagrams.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Pencil Project is a free, open-source desktop application for GUI mockups, wireframes, flowcharts, and other diagrams. It is intended for people who need to sketch interfaces or create straightforward visual documentation on Windows, macOS, or GNU/Linux. Built-in collections cover general-purpose shapes, desktop and web interfaces, Android, and iOS, while connectors, freehand drawing, and object snapping support basic diagram construction. Inter-page linking also allows users to create interactive HTML prototypes.
Its strongest advantage is the combination of a free open-source model and broad export coverage. Documents can be exported as PNG, HTML/web, OpenDocument text, SVG, or PDF, and SVG can be imported. Custom stencil collections extend the built-in shape library, while clipart browser integration with OpenClipart.org adds another source of visual elements. These capabilities make Pencil Project a practical fit for interface planning, flowcharts, and diagrams that need to move into documents, vector files, PDFs, or web prototypes.
The trade-off is focus. Pencil Project is centered on desktop-based mockups and basic diagrams rather than a broader collaborative diagramming workspace. Its published feature set emphasizes drawing, shape libraries, connectors, prototyping, and file export, so teams seeking shared editing or version history should consider a different type of tool. Choose Pencil Project when free, cross-platform wireframing and local diagram creation are the priority; choose an alternative when real-time collaboration or more extensive team workflow features matter more.
Pencil Project pros and cons
- Where it wins
- Free and open source across Windows, macOS, and GNU/Linux
- Built-in shape collections cover UI mockups, flowcharts, and mobile interfaces
- Exports to PNG, HTML, SVG, PDF, and OpenDocument text
- Where it doesn't
- Desktop-focused rather than a browser-based diagram workspace
- More focused on mockups and basic diagrams than broad diagramming
- No collaboration or version-history features are listed
Pencil Project fact sheet, pricing and score →
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