[opensourcedex]

best-of ranking · updated nightly

Best Open Source Design & Prototyping Tools

Ranked by GitHub stars — actual adoption, not editorial taste. All 5 are free, open source and self-hostable; license and last activity on every entry.

  1. 1
    OpenPencil ★ 8.4K

    Design editor that opens Figma files, runs AI, and stays local

    MIT TypeScript pushed 2026-09-17 details →
  2. 2
    draw.io ★ 8.2K

    Security-first diagramming with no login required

    Apache-2.0 JavaScript pushed 2026-09-16 details →
  3. 3
    Plasmic ★ 7.0K

    Visual app builder that integrates with your existing codebase

    MIT TypeScript pushed 2026-09-17 details →
  4. 4
    Quant-UX ★ 2.7K

    Design, prototype, and test user experiences with ease

    GPL-3.0 Vue pushed 2026-09-15 details →
  5. 5
    Grida ★ 2.6K

    Open canvas for designing and building web apps

    Apache-2.0 TypeScript pushed 2026-09-17 details →
method stars desc · snapshot from github api refresh nightly related Finance & Fintech, Logistics & Supply Chain, Media & Streaming, Photo & Video Editors, Gaming, Internet of Things (IoT)

Related best-of lists

best Finance & Fintech →best Logistics & Supply Chain →best Media & Streaming →best Photo & Video Editors →best Gaming →best Internet of Things (IoT) →

last updated nightly · ranking method: github stars, live-tracked

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Frequently asked questions

What is the best open source Design & Prototyping tool in 2026?

OpenPencil leads the ranking with 8,357 GitHub stars, ahead of draw.io. Rankings use live GitHub star counts, refreshed nightly.

How is this list of Design & Prototyping tools ranked?

By GitHub stars — a proxy for adoption and community size. Each entry also shows its licence, primary language and last commit date, so you can judge maintenance activity rather than trusting the ranking alone.

Are the best Design & Prototyping tools free?

Every project on this list is open source and free to self-host. Some also offer paid managed hosting, but the software itself carries no licence fee.