Best Open-Source Wireframe Tools 2026: 6 Options Compared

Open-source wireframing is a small field, so it helps to know what each tool is built for. Penpot is the closest to commercial design apps: MPL-2.0, browser-based, with components and prototypes, and you can self-host it. Pencil Project is a GPL-2.0 desktop wireframing and prototyping tool for Windows, macOS and Linux that keeps stencils on your computer and has no account system. Quant-UX is a GPL-3.0 tool for prototyping and usability testing, which is useful if you want to watch how users click through a flow, but it needs a separate Java backend if you host it yourself. Draw.io and Excalidraw are general diagram and sketch tools that many teams use for wireframes because they are fast and have no sign-up. Inkscape works if you prefer drawing screens as vector art. The trade-off is polish against speed. Penpot gives the most reusable design system, while Excalidraw produces rough layouts that encourage discussion about structure rather than colour. If you need testing with real users, Quant-UX is the one purpose-built for it. Whichever you pick, store wireframes as exportable files so the work outlives the tool.

Penpot

MPL-2.0, self-hostable browser design tool with components and prototypes; free plan up to 8 team members. The most complete open option.

Price: Free (Professional plan at $0: up to 8 team members plus unlimited viewers, 10GB storage, 7 days of version history); paid from $7 per per editor/month (Unlimited), capped at $175/month; 14-day free trial (Penpot pricing, checked 2026-10-23).

Platforms and license: Web. MPL-2.0 (open source) (license source).

Project activity: 61.8k GitHub stars · latest release 2.18.5 (Oct 26, 2026) · last commit Oct 27, 2026

Best for: Wireframes that grow into designs.

Pencil Project

GPL-2.0 desktop prototyping tool for Windows, macOS and Linux with stencil sets and no accounts. No live collaboration.

Price: Free (Free, open-source desktop prototyping tool; no price listed) (Pencil Project pricing, checked 2026-10-23).

Platforms and license: Windows, macOS, Linux. GPL-2.0 (open source) (license source).

Project activity: 9.9k GitHub stars · latest release v4.0.0 (Oct 24, 2026) · last commit Oct 27, 2026

Best for: Offline wireframing.

Worth knowing: README shows ongoing development with v4.0 adding MCP support.

Quant-UX

GPL-3.0 prototyping and usability testing tool; self-host with Docker or Kubernetes, front-end repo needs a separate backend.

Price: Free (Open source and self-hostable; quant-ux.com is described only as a demo; front-end repo needs the separate qux-java backend) (Quant-UX pricing, checked 2026-10-23).

Platforms and license: Web, Self-hosted (Docker, Kubernetes). GPL-3.0 (open source) (license source).

Project activity: 2.7k GitHub stars · last commit Oct 11, 2026

Best for: Testing wireframes with real users.

Worth knowing: Research, usability testing and prototyping rather than pure wireframing.

draw.io (diagrams.net)

Apache-2.0 diagram editor with mockup shape libraries, free without sign-up. Good for static screens, with limited interactivity compared with a prototyping tool.

Price: Free (Free with no sign-up; open files from local storage or your own cloud account) (draw.io (diagrams.net) pricing, checked 2026-10-22).

Platforms and license: Web, Windows, macOS, Linux. Apache-2.0 (open source) (license source).

Project activity: 9k GitHub stars · latest release v32.6.1 (Oct 23, 2026) · last commit Oct 23, 2026

Best for: Quick static wireframes.

Compare: draw.io (diagrams.net) alternatives

Excalidraw

MIT web whiteboard with a hand-drawn look and real-time collaboration. It has no component system, so reuse across screens means copying shapes.

Price: Free (Free web app with real-time collaboration and end-to-end encryption); paid from $6 per user/month, Excalidraw+ (Excalidraw pricing, checked 2026-10-22).

Platforms and license: Web. MIT (open source) (license source).

Project activity: 134.7k GitHub stars · latest release v0.18.1 (Apr 21, 2026) · last commit Oct 27, 2026

Best for: Rough layouts for feedback.

Worth knowing: Excalidraw+ has a 14-day trial; annual billing saves 14%. Hand-drawn look, not a formal-shape library.

Inkscape

GPL-3.0 vector editor for Linux, macOS and Windows. Flexible for custom screens but has no wireframe-specific tools.

Price: Free (Free software under GPLv3; the site asks for donations and lists no paid tier) (Inkscape pricing, checked 2026-10-22).

Platforms and license: Linux, macOS, Windows. GPL-3.0 (open source) (license source).

Project activity: 4.1k GitHub stars · No commits since Mar 3, 2022

Best for: Designers who prefer vector drawing.

Worth knowing: SVG vector editor. The site links to the GPLv3 guide; the GPLv3 license name is taken from that link.

Which one to pick

• You want wireframes to become final designs: Penpot
• You work offline on a desktop: Pencil Project
• You want to test screens with users: Quant-UX
• You need a quick rough layout with a team: Excalidraw