A lightweight TypeScript library that converts Markdown files into styled PDF documents. Built on marked for parsing and PDFKit for PDF generation. README.pdf | Live Demo
-
- Headings (h1–h6) with configurable fonts, sizes, and colors
- Inline formatting — bold, italic, bold-italic, strikethrough, inline code
- Code blocks with monospace font and background shading
- Blockquotes with colored left border
- Lists — ordered and unordered, with nested sub-lists
- Tables with header row highlighting and cell borders
- Links rendered as clickable PDF hyperlinks
- Images — local (PNG, JPEG) and remote (HTTP/HTTPS) with automatic SVG-to-PNG conversion via @resvg/resvg-js
- Mermaid diagrams — render
mermaidfenced code blocks as diagrams (flowchart, sequence, class, state, ER, gantt, pie, mindmap) via @speajus/mermaid-to-svg - Horizontal rules
- Automatic page breaks when content exceeds the current page
- Fully themeable — customize fonts, colors, spacing, page size, and margins
npm install @speajus/markdown-to-pdfConvert a Markdown file to PDF from the command line:
# Run directly with npx (no install needed)
npx @speajus/markdown-to-pdf <input.md> [output.pdf]
# Or if installed globally / as a project dependency
markdown-to-pdf <input.md> [output.pdf]If the output path is omitted, the PDF is written alongside the input file with a .pdf extension.
# Converts README.md → README.pdf
npx @speajus/markdown-to-pdf README.md
# Explicit output path
npx @speajus/markdown-to-pdf docs/report.md output/report.pdfimport { generatePdf } from '@speajus/markdown-to-pdf';
// Returns a PDF Buffer
const markdown = '# Hello World\n\nThis is a **test**.';
const pdfBuffer = await generatePdf(markdown);
// With options
import { generatePdf, createNodeImageRenderer } from '@speajus/markdown-to-pdf';
const buffer = await generatePdf(markdown, {
basePath: '/path/to/markdown/directory',
renderImage: createNodeImageRenderer('/path/to/markdown/directory'),
});The samples/ directory contains example Markdown files. Generate PDFs for all of them at once:
npm run generateOutput is written to the output/ directory.
Both generatePdf and renderMarkdownToPdf accept an optional PdfOptions object:
interface PdfOptions {
theme?: ThemeConfig; // Typography, colors, and component styles
pageLayout?: PageLayout; // Page size and margins
basePath?: string; // Base directory for resolving relative image paths
syntaxHighlight?: boolean; // Enable syntax highlighting (default: true)
lineNumbers?: boolean; // Show line numbers in code blocks (default: false)
languages?: string[]; // Prism.js languages to load (default: all)
zebraStripes?: boolean; // Zebra-stripe table rows (default: true)
}Fenced code blocks with the language mermaid are automatically rendered as diagrams:
```mermaid
flowchart TD
A[Start] --> B{Decision}
B -->|Yes| C[Process A]
B -->|No| D[Process B]
C --> E[End]
D --> E
```Mermaid theme colors are integrated with the PDF theme. Each built-in theme includes matching mermaid colors. You can also customize them:
await generatePdf(markdown, {
theme: {
...defaultTheme,
// Use a built-in mermaid theme
mermaid: 'forest', // 'default' | 'dark' | 'forest' | 'neutral'
},
});
// Or provide custom mermaid colors
await generatePdf(markdown, {
theme: {
...defaultTheme,
mermaid: {
background: '#ffffff',
primaryColor: '#4a90d9',
secondaryColor: '#b8d4f0',
lineColor: '#333333',
primaryTextColor: '#1a1a1a',
borderColor: '#4a90d9',
},
},
});Supported diagram types: flowchart, sequence, class, state, ER, gantt, pie, and mindmap.
import { generatePdf } from '@speajus/markdown-to-pdf';
await generatePdf(markdown, {
pageLayout: {
pageSize: 'A4',
margins: { top: 72, right: 72, bottom: 72, left: 72 },
},
});The default layout uses Letter page size with 50pt margins on all sides.
Override any part of the default theme to customize the look of the generated PDF:
import { generatePdf, defaultTheme } from '@speajus/markdown-to-pdf';
await generatePdf(markdown, {
theme: {
...defaultTheme,
headings: {
...defaultTheme.headings,
h1: { font: 'Helvetica-Bold', fontSize: 32, color: '#0a3d62', bold: true },
},
linkColor: '#e74c3c',
},
});The full ThemeConfig interface exposes styles for:
| Section | Configurable properties |
|---|---|
| headings | Font, size, and color for each level (h1–h6) |
| body | Font, size, color, and line gap |
| code.inline | Font, size, color, and background color |
| code.block | Font, size, color, background color, and padding |
| blockquote | Border color, border width, italic flag, and indent |
| table | Header background, border color, cell padding, and zebra color |
| linkColor | Color for hyperlink text |
| horizontalRuleColor | Color for --- dividers |
| mermaid | Diagram colors: primary, secondary, text, line, border, background |
├── src/
│ ├── index.ts # Public API — generatePdf, renderMarkdownToPdf, exports
│ ├── cli.ts # Command-line entry point
│ ├── renderer.ts # Markdown-to-PDF rendering engine
│ ├── mermaid-renderer.ts # Mermaid diagram → PNG rendering
│ ├── styles.ts # Default theme and page layout
│ ├── themes/index.ts # Built-in theme variants
│ └── types.ts # TypeScript interfaces for options and theming
├── samples/
│ ├── generate.ts # Script to batch-generate sample PDFs
│ ├── sample.md # Full-featured sample document
│ ├── mermaid.md # Mermaid diagram examples (all diagram types)
│ ├── image.md # Image rendering tests (local, remote, SVG, broken)
│ ├── logo.svg # Sample SVG image
│ ├── logo.png # Sample PNG image
│ └── sample.png # Sample raster image
├── output/ # Generated PDF output directory
├── package.json
└── tsconfig.json
| Package | Purpose |
|---|---|
| marked | Markdown parsing and tokenization |
| pdfkit | PDF document generation |
| @resvg/resvg-js | SVG-to-PNG rasterization for image embedding |
| @speajus/mermaid-to-svg | Mermaid diagram rendering (parse → layout → SVG) |
| Command | Description |
|---|---|
| npm run build | Compile TypeScript to dist/ |
| npm run generate | Generate sample PDFs from samples/*.md into output/ |
ISC