pdfkit-client

Client-side .pptx and .xlsx → PDF conversion. No server. No uploads. Pure browser.

Why

Every other solution either requires a server, sends your files to a third party, or is abandonware. This library runs entirely in the browser using the File API, JSZip, and jsPDF.

Trade-off you should know about: Fidelity is ~70-80% on complex files. Charts, advanced animations, and exotic fonts won't transfer. Simple-to-moderate presentations and spreadsheets work well.

Install

npm install @ozh1n/pdfkit jszip jspdf

Or via CDN:

<script src="https://unpkg.com/jszip/dist/jszip.min.js"></script>
<script src="https://unpkg.com/jspdf/dist/jspdf.umd.min.js"></script>
<script src="https://unpkg.com/@ozh1n/pdfkit/dist/index.umd.js"></script>

Usage

Basic

import { toPDF } from 'pdfkit-client'

const input = document.querySelector('input[type="file"]')
input.addEventListener('change', async () => {
  const file = input.files[0]
  const result = await toPDF(file)

  if (result.ok) {
    result.pdf.download('output.pdf')   // triggers browser download
  } else {
    console.error(result.error)
  }
})

With options

const result = await toPDF(file, {
  pages:       [0, 1, 2],       // only first 3 pages/sheets
  pageNumbers: true,            // add page numbers
  title:       'My Document',  // PDF metadata
})

Access the PDF as a Blob (for upload, preview, etc.)

const result = await toPDF(file)
if (result.ok) {
  const blob    = result.pdf.toBlob()      // Blob
  const dataUrl = result.pdf.toDataUrl()   // base64 string for <iframe src>
}

Inspect the Intermediate Representation

import { toIR } from 'pdfkit-client'

const ir = await toIR(file)
if (ir.ok) {
  console.log(ir.doc.pages.length, 'pages')
  console.log(ir.doc.pages[0].elements)   // all parsed elements
}

Supported formats

| Format | Support | Notes | |--------|---------|-------| | .pptx | ✅ | Text, images, shapes, tables | | .xlsx | ✅ | Cell data, basic styles, multiple sheets | | Charts | ⚠️ planned v0.2 | | | Animations | ❌ never | PDF is static | | Complex formulas | ⚠️ values only | Formula results are preserved |

Architecture

File (.xlsx / .pptx)
    ↓
JSZip → unzip in memory
    ↓
Format Parser → Intermediate Representation (IR)
    ↓
PDF Generator (jsPDF) → PDF Blob
    ↓
Download / Blob / DataURL

The IR is a format-neutral data model. This separation means:

• Parsers are independently testable
• You can write custom renderers (e.g. HTML preview, PNG export)
• The public toIR() API lets you build on top of the parsed data

Contributing

git clone https://github.com/aryan1jain2/pdfkit
npm install
npm run dev      # demo app at localhost:5173
npm test         # unit tests
npm run build    # produces dist/

PRs welcome, especially for:

• Chart rendering
• Better font substitution
• PPTX theme colour resolution
• Merged cell support in XLSX

License

MIT