n8n-nodes-pdf-compress

Compress PDF files in n8n workflows using Ghostscript compiled to WebAssembly. This node is free, requires no API key or external service, and runs purely in Node.js—no system Ghostscript install needed.

Features

• Free & no API: No sign-up, API key, or third-party service. Everything runs locally in your n8n instance.
• Pure JS/WASM: Works in any n8n environment (Docker, Cloud, Desktop) without additional system dependencies.
• Ghostscript Power: Uses the industry-standard Ghostscript engine (via @okathira/ghostpdl-wasm) for high-quality compression.
• Compression Presets: Choose between different quality/size trade-offs (Screen, Ebook, Printer, Prepress, Default).

Presets

• Screen: Lowest quality, smallest file size (72 dpi). Ideal for web viewing.
• Ebook: Medium quality, medium file size (150 dpi). Good balance for reading on devices.
• Printer: High quality (300 dpi). Suitable for home/office printing.
• Prepress: Highest quality (300 dpi). Preserves color and quality for professional printing.
• Default: Standard Ghostscript compression settings.

Usage in n8n

1. Add the PDF Compress node to your workflow.
2. Select the Binary Property where your PDF is located (default: data).
3. Choose a Compression Quality preset.
4. The node will output the compressed PDF in the same binary property (with .compressed.pdf suffix) and add compression stats to the JSON output.

JSON Output Example

{
  "pdfCompress": {
    "originalSizeBytes": 12110000,
    "compressedSizeBytes": 1240000,
    "percentageSaved": "89.76%",
    "presetUsed": "/screen"
  }
}

Developer Notes

This node was built using:

• n8n Node SDK
• @okathira/ghostpdl-wasm

To test locally:

node scripts/test-compress.mjs <path-to-pdf>

License

This project is licensed under the AGPL-3.0-or-later license. This is required because the project depends on Ghostscript (via @okathira/ghostpdl-wasm), which is also licensed under the AGPL. See the LICENSE file for details.