Automatically Add Watermarks to PDFs in Google Drive Using n8n and PDF.co

Oct 9, 2025·6 Minutes Read

What You’ll Have When Done

You’ll have a fully automated system that watches a Google Drive folder for new PDF uploads, automatically adds a watermark or custom label using PDF.co, and then saves the processed (watermarked) file into another Google Drive folder — all hands-free.

Prerequisites

Before you begin, make sure you have:

  • Two Google Drive folders:
    • Input Folder – where new PDFs are uploaded (e.g., “INPUT_FOLDER”)
    • Output Folder – where processed PDFs will be saved (e.g., “OUTPUT_FOLDER”)
  • n8n instance (either self-hosted or n8n.cloud).
  • PDF.co API Keyhttps://app.pdf.co/
  • Google Drive OAuth2 credentials added in n8n.

Quick Start Options

Option A: I Want It Working Now

  1. Import this workflow template(Download JSON File)
  2. Connect your Google Drive and PDF.co accounts in n8n.
  3. Link your Google Drive folders (input and output).
  4. Update watermark text or placement if needed.
  5. Run a test: upload a PDF to your input folder and watch it automatically get watermarked and saved to the output folder.

Option B: I Want to Build It Step-by-Step

Follow this detailed guide to create the automation from scratch.

What This Automation Does

Here’s the overview of the workflow:

  1. Google Drive Trigger → Detects when a new file is uploaded to your selected folder.
  2. PDF.co API → Adds a watermark or text overlay to the file.
  3. HTTP Request → Downloads the newly watermarked PDF.
  4. Google Drive Upload → Uploads the processed file to your chosen folder.

Step-by-Step Guide

Step 1: Set Up Google Drive Folders

Create two folders in your Google Drive:

  • INPUT_FOLDER → PDFs uploaded here will trigger the automation.
  • OUTPUT_FOLDER → Processed (watermarked) PDFs will be saved here.

Your structure:

📁 Google Drive

├── INPUT_FOLDER

└── OUTPUT_FOLDER

Success Looks Like: Both folders are created, and you can copy their folder IDs from their Google Drive URLs.

Step 2: Add Google Drive Trigger Node

Node: Google Drive Trigger

Settings:

  • Trigger On: Specific Folder
  • Folder to Watch: INPUT_FOLDER
  • Event: File Created
  • Poll Time: Every Minute

Success Looks Like: Each time you upload a new PDF to your input folder, the workflow starts automatically.

Step 3: Add Text or Watermark Using PDF.co

Node: PDF.co API → Add Text/Images to PDF

This node takes the uploaded PDF and applies your watermark.You can run your test with this sample file

Settings:

  • URL: ={{ $json.webContentLink }}

Text Annotation Example:

 {
  "text": "GEC",
  "x": "104.6",
  "y": "412.33",
  "size": "100",
  "color": "#2563EB66",
  "fontBold": true,
  "fontName": "Arial Black",
  "alignment": "center"
}

Understanding the Color and Opacity

#2563EB66 is an 8-digit HEX code that defines both the color and the opacity of your watermark:

  • The first 6 digits (#2563EB) represent the base color – a bright blue.
  • The last 2 digits (66) represent the opacity (transparency level) in hexadecimal.
Hex Values

Therefore, #2563EB66 means blue color (#2563EB) with around 40% transparency, keeping your watermark visible yet subtle.

This visual tool makes watermark positioning effortless:

  1. Upload your PDF template or sample file.
  2. Draw a rectangle over the area where you want your watermark text or image to appear.
  3. The tool automatically generates the coordinates (X, Y), width, height, font size, and other parameters.
  4. Copy those values directly into your n8n node configuration.

This saves you from manually trial-and-error testing positions — it’s quick, accurate, and visual.

Advanced Options:

  • Output File Name: ={{ $json.name }}

Success Looks Like: PDF.co returns a JSON response containing the URL to your new, watermarked file:

{

"url": "https://pdf-co-temp-files.s3.amazonaws.com/Watermarked_File.pdf",

"name": "Watermarked_MyDocument.pdf"

}

Step 4: Download the Watermarked PDF

Node: HTTP Request

Settings:

  • Method: GET
  • URL: ={{ $json.url }} (from the PDF.co node output)

Success Looks Like: n8n retrieves the binary file of the watermarked PDF from PDF.co.

Step 5: Upload the Watermarked PDF to Google Drive

Node: Google Drive → Upload

Settings:

  • Input Data Field: data
  • File Name: Watermarked_{{ $json.name }}
  • Folder: OUTPUT_FOLDER (select your output folder)
  • Drive: My Drive

Success Looks Like: The watermarked PDF automatically appears in your OUTPUT_FOLDER folder in Google Drive.

Step 6: Test the Automation

  1. Upload any PDF file into your INPUT_FOLDER folder.
  2. Wait for 30–60 seconds for the trigger to detect it.
  3. Watch as:
    • PDF.co processes the file and applies the watermark.
    • The final version appears in your OUTPUT_FOLDER folder.

Success Looks Like: Each time you upload a file, it’s automatically processed and watermarked — no manual steps needed.

Step 7: Optional — Batch or Scheduled Watermarking

Want to process multiple files at once or run on a schedule?

  • Replace the Google Drive Trigger with a Schedule Trigger.
  • Add a Google Drive → List Files node to retrieve all files in your folder.

This setup is perfect for nightly batch watermarking or compliance document processing.

Congratulations!

You’ve just built an automation that:

  • Detects new PDFs in Google Drive
  • Adds custom text or logo watermarks with PDF.co
  • Uploads the processed version back to your chosen folder
  • Runs continuously without manual effort

Next Steps

You can enhance this automation further by:

  • Sending an email notification once watermarking is complete.
  • Logging processed file names in a Google Sheet.
  • Using variables like upload date, user name, or document type in your watermark text.

Built something amazing? Share your workflow and tag us @pdfdotco — we’d love to feature your automation!

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