tinypdf

Install the tinypdf library using npm to start creating minimal PDFs with zero dependencies.

npm install tinypdf

To create a basic PDF, import pdf from tinypdf, initialize a document, and use doc.page() to define a drawing context. Within the callback, you can use methods like ctx.rect, ctx.text, and ctx.line to draw elements. Finally, call doc.build() to get a Uint8Array of the PDF content.

import { pdf } from 'tinypdf'
import { writeFileSync } from 'fs'

const doc = pdf()

doc.page((ctx) => {
  ctx.rect(50, 700, 200, 40, '#2563eb')           // blue rectangle
  ctx.text('Hello PDF!', 60, 712, 24, { color: '#ffffff' })
  ctx.line(50, 680, 250, 680, '#000000', 1)       // black line
})

writeFileSync('output.pdf', doc.build())

For documents that are too large to fit in memory, use doc.buildStream() instead of doc.build(). This returns a ReadableStream<Uint8Array> that emits the PDF data one object at a time, making it suitable for writing to disk or serving via HTTP.

import { pdf } from 'tinypdf'

const doc = pdf()
for (let i = 0; i < 10_000; i++) {
  doc.page((ctx) => ctx.text(`Page ${i + 1}`, 50, 750, 12))
}

// Write to disk (Bun)
await Bun.write('huge.pdf', doc.buildStream())

// Or serve as an HTTP response
return new Response(doc.buildStream(), {
  headers: { 'Content-Type': 'application/pdf' },
})

To add a clickable URL, use ctx.link(url, x, y, w, h, options?). A common pattern is to use measureText to determine the width of the text being linked to ensure the clickable area matches the text size.

import { pdf, measureText } from 'tinypdf'

doc.page((ctx) => {
  const text = 'Visit Example.com'
  const y = 700
  ctx.text(text, 50, y, 14, { color: '#0066cc' })
  ctx.link('https://example.com', 50, y - 4, measureText(text, 14), 18, { underline: '#0066cc' })
})

You can add JPEG images to a page using ctx.image(). This method requires a Uint8Array of the JPEG bytes.

import { readFileSync } from 'fs'

doc.page((ctx) => {
  const logo = new Uint8Array(readFileSync('logo.jpg'))
  ctx.image(logo, 50, 700, 100, 50)
})

Use measureText(str, size) to calculate the width of a string in points for a given font size. This is useful for alignment and calculating link bounding boxes.

import { measureText } from 'tinypdf'

measureText('Hello', 12) // => 27.34 (points)

The markdown(str, options?) function allows you to generate a PDF directly from a markdown string. It supports headers (h1, h2, h3), bullet lists, numbered lists, and horizontal rules. It includes automatic word wrapping and pagination.

Options include width, height, and margin.

import { markdown } from 'tinypdf'
import { writeFileSync } from 'fs'

const pdf = markdown(`
# Hello World

A minimal PDF from markdown.

## Features
- Headers (h1, h2, h3)
- Bullet lists
- Numbered lists
- Horizontal rules

---

Automatic word wrapping and pagination included.
`)

writeFileSync('output.pdf', pdf)

Standalone utility functions.

measureText(str, size)                     // text width in points
markdown(str, options?)                    // options: { width, height, margin }

Methods available within the doc.page callback to draw elements on the page.

ctx.text(str, x, y, size, options?)        // options: { color, align, width }
ctx.rect(x, y, w, h, fill)                 // filled rectangle
ctx.line(x1, y1, x2, y2, stroke, width?)   // line
ctx.image(jpegBytes, x, y, w, h)           // JPEG image
ctx.link(url, x, y, w, h, options?)        // options: { underline }

Methods for managing the PDF document and its pages.

pdf()                                      // create document
doc.page(callback)                         // add page (612×792 default)
doc.page(width, height, callback)          // add page with custom size
doc.build()                                // returns Uint8Array
doc.buildStream()                          // returns ReadableStream<Uint8Array>

Insert a JPEG image into the page.

Parameters:

• jpegBytes: A Uint8Array containing the JPEG data.
• x: X-coordinate.
• y: Y-coordinate.
• w: Width.
• h: Height.

A high-level utility to convert a Markdown string directly into a Uint8Array PDF document.

Parameters:

• md: The Markdown string.
• opts?: { width?: number; height?: number; margin?: number }: Document dimensions and margins. Defaults are width: 612, height: 792, and margin: 72.

Supported Markdown Features:

• Headers (# to ######)
• Lists (-, *, or 1. )
• Horizontal rules (---, ***, or ___)
• Paragraphs
• Blank lines