LibreOffice WASM Document Converter

Convert documents between formats (DOCX, PDF, XLSX, PPTX, etc.) in Node.js or browsers using LibreOffice compiled to WebAssembly. No native dependencies required.

Features

• Pure WebAssembly - No native LibreOffice installation required
• Wide Format Support - Convert between 15+ document formats
• Cross-Platform - Works in Node.js and browsers
• Fast - ~35ms per conversion after initialization

Installation

npm install @matbee/libreoffice-converter

Demo

https://convertmydocuments.com

Quick Start

One-Shot Conversion (Simplest)

import { convertDocument } from '@matbee/libreoffice-converter';
import fs from 'fs';

const docx = fs.readFileSync('document.docx');
const result = await convertDocument(docx, { outputFormat: 'pdf' });
fs.writeFileSync('document.pdf', result.data);

Export as Image

import { exportAsImage } from '@matbee/libreoffice-converter';
import fs from 'fs';

// Export single page (0-indexed)
const [cover] = await exportAsImage(docxBuffer, 0, 'png');
fs.writeFileSync('cover.png', cover.data);

// Export multiple pages
const slides = await exportAsImage(pptxBuffer, [0, 1, 2], 'png');
slides.forEach((img, i) => fs.writeFileSync(`slide-${i}.png`, img.data));

// Export with options
const highRes = await exportAsImage(pptxBuffer, [0, 1, 2], 'png', { dpi: 300, width: 1920 });

Server Usage (Recommended)

For servers, use the worker converter to avoid blocking the main thread:

import { createWorkerConverter } from '@matbee/libreoffice-converter';

const converter = await createWorkerConverter({ wasmPath: './wasm' });

// Reuse for multiple conversions
const pdf = await converter.convert(docxBuffer, { outputFormat: 'pdf' });
const csv = await converter.convert(xlsxBuffer, { outputFormat: 'csv' });

await converter.destroy(); // Clean up when done

Supported Formats

Input: doc, docx, xls, xlsx, ppt, pptx, odt, ods, odp, rtf, txt, html, csv, pdf, epub

Output: pdf, docx, doc, odt, rtf, txt, html, xlsx, xls, ods, csv, pptx, ppt, odp, png, jpg, svg

Browser Usage

import { WorkerBrowserConverter, createWasmPaths } from '@matbee/libreoffice-converter/browser';

const converter = new WorkerBrowserConverter({
  ...createWasmPaths('/wasm/'),
  browserWorkerJs: '/dist/browser.worker.js',
  onProgress: (info) => console.log(`${info.percent}%: ${info.message}`),
});

await converter.initialize();

const result = await converter.convert(fileData, { outputFormat: 'pdf' }, 'doc.docx');

// Download result
const blob = new Blob([result.data], { type: result.mimeType });
const url = URL.createObjectURL(blob);
const a = document.createElement('a');
a.href = url;
a.download = result.filename;
a.click();

Required HTTP headers for SharedArrayBuffer:

Cross-Origin-Opener-Policy: same-origin
Cross-Origin-Embedder-Policy: require-corp

Documentation

• API Reference - Complete API documentation, types, configuration options
• Examples - Express server, React component, batch conversion, and more

System Requirements

• Node.js 18.0.0+
• ~150MB disk space for WASM files
• Browser: ~240MB initial download (cached after first load)

License

MPL-2.0 (same as LibreOffice)

Contributing

git clone https://github.com/matbeedotcom/libreoffice-document-converter.git
cd libreoffice-document-converter
npm install
npm run build
npm test

See docs/API.md#building-from-source for building the WASM module.