Markdown to PDF

Mobile-friendly Markdown to PDF in your browser with GFM, syntax highlighting, and Mermaid. Works offline; nothing is uploaded for conversion.

Live app: md2pdf.marcopontili.com

Acknowledgements

This repository is derived from realdennis/md2pdf (MIT). Thanks to Dennis for the original app.

This fork is maintained on its own track: Mermaid preview, GFM + highlighted code, offline PWA, tighter sanitization, print-friendly styling, CI/deploy, and tests.

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Features

• Convert Markdown to PDF via the browser print dialog
• 100% offline: works without internet after first load
• Client-only workflow: no backend; Markdown is rendered and printed from your browser session
• Privacy-friendly: conversion runs locally; nothing is sent to an app server for processing
• Responsive / mobile: tabbed Editor and Preview on narrow viewports; split editor + preview on desktop
• PWA support (installable, cache-first for repeat visits)
• Custom styles for PDF output (GitHub-style markdown CSS)
• Instant live preview and syntax-highlighted code blocks
• Mermaid diagrams from fenced mermaid code blocks
• Import .md files via button or drag-and-drop

Tech Stack

• React 19 with Vite
• styled-components for styling
• CodeMirror 6 (@uiw/react-codemirror) for the editor
• react-markdown + remark-gfm + highlight.js for markdown rendering
• vite-plugin-pwa (Workbox-powered) for the service worker (offline/caching)
• nonaction for minimal state

Security

• Local-first / privacy: Markdown and preview live in your browser; there is no backend that receives your document for conversion.
• No raw HTML in markdown: the preview renders markdown only; raw HTML in .md is not executed, which prevents XSS from untrusted content.
• Strict file handling: only .md files are accepted on import; content is read with the File API and never sent over the network.
• Security headers: when served with Apache, the app uses safe defaults (e.g. X-Content-Type-Options: nosniff, no directory listing, blocked access to hidden and backup files). Optional headers (X-Frame-Options, Referrer-Policy) are documented in public/.htaccess.

Installation

1. Clone the repository:

   git clone https://github.com/marcop135/md2pdf.git
   cd md2pdf

2. Install dependencies:

   yarn install

3. Run locally:

   yarn start

   Then open http://localhost:5173; the terminal also prints the Local: URL.

   If startup fails because 5173 is in use, another process already bound that port (often a stray Vite terminal). Quit that session or kill the orphaned process so the app serves on 5173 consistently.

4. Production build:

   yarn build

   Output is in the dist/ folder. Serve it with any static host (e.g. Apache, Nginx, or a static hosting service). For Apache, copy public/.htaccess to the root of the deployed site for recommended security and caching.

Usage

• Type or paste Markdown in the editor.
• Use the Preview tab (on mobile) or the right panel (on desktop) to see the rendered result.
• Click Export to .pdf to open the print dialog; choose “Save as PDF” (or equivalent) to get a PDF.
• Use Import .md file or drag-and-drop a .md file to load its content.

Mermaid example (marketing-site flow):

flowchart TD
  A[Channels] --> B[Landing]
  B --> C[Hero + offer]
  C --> D[Social proof]
  D --> E{Intent}
  E -->|Research| F[Inner pages]
  E -->|Ready| G[CTA]
  F --> G
  G --> H[Convert]
  H --> I[Activation]
  I --> J[Retention]

  classDef acquire fill:#dbeafe,stroke:#2563eb,color:#1e3a8a
  classDef engage fill:#ede9fe,stroke:#7c3aed,color:#4c1d95
  classDef decide fill:#fef3c7,stroke:#d97706,color:#78350f
  classDef convert fill:#d1fae5,stroke:#059669,color:#065f46
  classDef grow fill:#cffafe,stroke:#0891b2,color:#0e7490

  class A,B acquire
  class C,D,F engage
  class E decide
  class G,H convert
  class I,J grow

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Project Structure

Path	Description
src/	Application source
src/App/	Root component, containers, layout
src/App/Components/	Header, Markdown editor, preview, drag bar
src/App/Container/	State (nonaction), hooks (e.g. useIsMobile, useDrop)
src/App/Lib/	Utilities (e.g. upload helper)
public/	Static assets (.htaccess, manifest.json, robots.txt)
dist/	Production output (after yarn build)

Scripts

Command	Description
yarn start	Development server
yarn build	Production build
yarn test	Run tests
yarn preview	Preview production build (dist/)
yarn hero:sync	Render social-preview SVGs to PNGs (og:image + GitHub repo card)
yarn changelog:lint	Validate CHANGELOG.md formatting

Contributing

Contributions welcome! Please read CONTRIBUTING.md for guidelines on how to contribute.

• Found a bug? Open an issue
• Have a feature request? Open an issue
• Want to contribute? Read the contributing guide

License

Licensed under the MIT License.