How to Programmatically Add Watermark to PDF, Tutorial

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Protect your documents, reinforce branding, and ensure compliance by learning how to programmatically add watermarks to PDFs using the pdfRest Watermark PDF API Tool. This versatile REST API tool enables developers to automate the process of applying either text-based or image-based watermarks to all pages of a PDF, with extensive customization options. If you're looking for a reliable solution to add watermarks to PDFs programmatically with precise control over font, size, color, opacity, scale, positioning, and rotation, pdfRest offers unparalleled flexibility and seamless integration.

Why Programmatically Add Watermark to PDF?

Document Security and Ownership: Programmatically apply watermarks to indicate document status (e.g., "Draft," "Confidential") or assert ownership, deterring unauthorized use.
Brand Reinforcement: Automatically embed company logos, branding elements, or legal notices into all outgoing PDFs, maintaining a consistent and professional image.
Automate Legal Compliance: Ensure regulatory adherence by programmatically embedding required disclaimers, copyrights, or confidential stamps into documents.
Track Document Distribution: Use dynamic watermarks to uniquely identify specific document copies, aiding in tracing leaks or unauthorized distribution.
Batch Processing Efficiency: Apply watermarks to a large volume of PDF documents automatically, saving significant manual effort and time.

Why Choose pdfRest API for Programmatic PDF Watermarking?

Supports Text and Images: Easily add both text-based watermarks (using watermark_text) and image-based watermarks (using watermark_file or watermark_file_id). For image files not in PDF format, seamlessly convert them first using the Convert to PDF API Tool.
Fully Customizable: Just like professional PDF editors, pdfRest provides full access to adjust your watermark with precision. Customize font, text size, color (RGB or CMYK), opacity, horizontal and vertical position (x, y offsets), and rotation.
Extensive Font Support: When applying a text watermark, choose from over 70 supported font options to find the perfect fit for your document.
Developer-Friendly API: Simple integration with clear documentation and consistent parameters across various programming languages.
Scalable and Reliable: Built for consistent performance, capable of handling high volumes of documents and complex watermarking requirements.
Secure Processing: Ensures the privacy and security of your PDF content throughout the watermarking process.
Comprehensive Support: Dedicated support team ready to assist with your integration needs.

How to Programmatically Add Watermark to PDF with pdfRest

Here's a simple example of how to use cURL to send a request to the pdfRest API to programmatically add a text watermark to a PDF with specific styling and positioning:

curl -X POST "https://api.pdfrest.com/watermarked-pdf" \
  -H "Accept: application/json" \
  -H "Content-Type: multipart/form-data" \
  -H "Api-Key: YOUR_API_KEY" \
  -F "file=@/path/to/your_document.pdf" \
  -F "watermark_text=CONFIDENTIAL" \
  -F "font=Helvetica" \
  -F "text_size=36" \
  -F "opacity=0.3" \
  -F "rotation=45" \
  -F "x=50" \
  -F "y=-50" \
  -F "output=document_with_watermark"

Replace YOUR_API_KEY with your actual pdfRest API key and adjust the file path and watermark parameters as needed. For image watermarks, you would use -F "watermark_file=@/path/to/your_image.pdf" instead of `watermark_text`.

Get Started Fast with Tutorials for Common Programming Languages

To help you integrate programmatically add watermark to PDF functionality into your specific development environment, we offer the following tutorials:

Try Watermarking Your PDFs Now in API Lab

Experience how easy it is to programmatically watermark PDFs directly in your browser using our API Lab. Upload your PDF, define your text or image watermark, set its properties (font, size, color, opacity, position, rotation), generate the code, send the API call, and download the watermarked PDF to validate the result.

Start Programmatically Protecting Your PDFs with Watermarks Today!

Enhance document security and branding by integrating the pdfRest API to programmatically add watermarks to PDF files. For detailed information on implementation and all available parameters, refer to our comprehensive API Documentation. Sign up for a free pdfRest account and start automating your PDF watermarking tasks today!