pdf watermark api

Here are a few common ways to add a watermark to a PDF via API, depending on your stack and whether you want a hosted service or a self-hosted library.

Popular PDF watermark API options

1) Adobe PDF Services API

Good for enterprise workflows.

• Add text/image watermarks
• Cloud-based
• Requires Adobe developer credentials

Docs: https://developer.adobe.com/document-services/

2) PSPDFKit / Nutrient API

Good for robust PDF processing.

• Watermarking
• Redaction, annotations, splitting/merging
• Cloud and on-prem options

Docs: https://www.nutrient.io/guides/pdf-api/

3) Apryse (formerly PDFTron)

Strong PDF SDK and server APIs.

• Watermark PDFs
• Very feature-rich
• Supports many platforms

Docs: https://docs.apryse.com/

4) iLovePDF API

Simple and easy for common PDF tasks.

• Add watermark
• Merge, split, compress, convert
• Straightforward REST API

Docs: https://developer.ilovepdf.com/

5) Smallpdf API

Also easy for common PDF automation.

• PDF watermarking
• Cloud API
• Good for lightweight integrations

Docs: https://smallpdf.com/developer

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If you want to build it yourself

You can also use libraries like:

• Python: pypdf, reportlab
• Node.js: pdf-lib
• Java: Apache PDFBox
• .NET: iText, Syncfusion PDF

Example idea with Python

1. Create watermark as a PDF overlay using reportlab
2. Merge overlay onto each page using pypdf

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Typical watermark API request flow

1. Upload PDF
2. Specify watermark text/image, opacity, rotation, position
3. Call API
4. Download processed PDF

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If you want, I can give you:

• a specific API recommendation
• a sample request in cURL / Python / Node.js
• or a DIY watermark script for your backend language.