# evolus/pencil

The Pencil Project's unique mission is to build a free and opensource tool for making diagrams and GUI prototyping that everyone can use.

Repository: https://github.com/evolus/pencil
Canonical: https://ross.abutalabs.com/products/pencil
Homepage: http://pencil.evolus.vn
Language: JavaScript
License: GPL-2.0
License Family: copyleft
Topics: pencil, nodejs, electron, sketching, ui-design, prototyping, javascript, mockup, drawing, wireframe
Last push: 2026-06-02T06:01:13+00:00

## Health v2 (maintenance only)
Score: 61/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 85, release rhythm 8, longevity 100
- inputs: {"age_days": 4458, "days_push": 92, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 9859, forks 790 (observed 2026-08-28T04:10:37.514408+00:00)

## What it is
Pencil is a free, open-source desktop application for GUI prototyping and diagram drawing, built on Electron. It ships with built-in shape collections for desktop, web, Android, and iOS UI mockups, plus flowchart shapes and export to PNG, PDF, SVG, and web pages.

## Use cases
- create wireframes for a web app
- prototype mobile app UI mockups
- draw flowcharts and diagrams
- export mockups to PDF or PNG
- sketch desktop application interfaces
- build clickable UI prototypes for free

## When to choose
- you need a free, cross-platform wireframing/prototyping tool
- you want built-in Android/iOS/desktop UI stencils
- you prefer offline desktop tools over web-based design apps
- you need simple diagram drawing with connector support

## When to avoid
- you need real-time team collaboration on designs
- you need high-fidelity interactive prototypes with animations
- you want a plugin ecosystem comparable to Figma or Sketch
- development pace is slow; cutting-edge features may be lacking

## Facets
- artifact type: application
- maturity: maintenance
- function: gui, graphics, documentation
- domain: web-design, developer-tools, graphics, cross-platform
- platform: cross-platform, windows
- tags: wireframing, prototyping, mockups, diagramming, ui-design, stencils, pdf-export, electron, macos, linux, nodejs

## Member repositories
- evolus/pencil (main) score 61

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:37.514408+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:20:53.270300+00:00, confidence not recorded.
  - readme: https://github.com/evolus/pencil (fetched 2026-08-28T04:10:37.514408+00:00, sha ea30d3f27d57)
  - homepage: http://pencil.evolus.vn (fetched 2026-08-29T08:20:36.423628+00:00, sha b60bb3b70fcd)
  - site_page: http://pencil.evolus.vn/Features.html (fetched 2026-08-29T08:20:36.432548+00:00, sha 9ddc9ce5c8bc)
- Data as of 2026-08-30T08:39:29.467469+00:00.