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Watermark PDF

Watermark PDF is a REST API tool that adds either a text-based or an image-based watermark to all pages of a PDF with customizable font, text size, color, opacity, scale, positioning, and rotation.

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Required Parameters
curl -X POST "https://api.pdfrest.com/watermarked-pdf" \ 
  -H "Accept: application/json" \ 
  -H "Content-Type: multipart/form-data" \
  -H "Api-Key: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" \
The response for your API Call will display here.
Once you've sent your POST request and received a valid response, you can download your output file using the output URL.

Why is pdfRest the best API to watermark PDF?

pdfRest offers the best solution for watermarking PDF documents, because it supports both text and images, full customization, and an extensive font list.

Supports Text and Images

Watermark PDF is your one-stop-shop to easily add both text-based watermarks and image-based watermarks to a PDF. Simply upload your PDF to be watermarked, and choose between uploading an image file (in PDF format) or setting the watermark_text field to use as your watermark. If your image file is in a different format than PDF, simply process it first with the Convert to PDF API Tool.

Fully Customizable

Just like Adobe® Acrobat™, Watermark PDF gives you full access to apply and adjust your watermark with precision.  For text-based watermarks, choose your font, text size, and text color.  For image-based watermarks, scale your image to any size.  For both text and image watermarks, adjust the opacity, vertical and horizontal position, and rotation value.

Extensive Font Support

When applying a watermark using text, choose from over 70 supported font options. Browse the Font List to find the best fit font for your watermark. If you don't see the font you're looking for, just let us know, and we'll be happy to look into the best ways to support your specific requirements.
Start from Code Examples
  1. First, you'll need an API Key - to:
    • Stay anonymous with a Guest API Key for 10 free API Calls
    • Sign up for an upgraded API Key with unlimited, continuous service
  2. Choose your programming language
  3. Copy and paste the code to your project
  4. Update Api-Key field with your unique API Key
  5. Update file with the local path to your input
  6. Run this code to send an API Call
See more code examples in our
GitHub repository
Try pdfRest with just a few clicks
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curl -X POST "https://api.pdfrest.com/watermarked-pdf" \
  -H "Accept: application/json" \
  -H "Content-Type: multipart/form-data" \
  -H "Api-Key: xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" \
  -F "file=@../Sample_Input/ducky.pdf" \
  -F "watermark_text=watermark" \
  -F "output=example_out"
Customize Your Solution
The watermark_file parameter lets you upload a PDF to pdfRest's processing server to be added as a watermark to your input document.

To add an image file as a watermark to a PDF, you can use pdfRest's Convert to PDF tool to convert a JPG, PNG, TIF, or BMP file to PDF and submit it here using the watermark_file or watermark_file_id parameter.

The following parameters allow you to further adjust your file watermark:
  • watermark_file_scale - apply a size multiplier to your file watermark
  • opacity - set watermark opacity
  • x and y - horizontal and vertical offset, respectively, from the center of the page
  • rotation - apply rotation to your watermark
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