API Tools
Watermark PDF

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.

A bubbling flask with code brackets inside

Try Now with API Lab

Start right from your browser - upload files, choose parameters, generate code, and send API Calls directly from API Lab!

to receive your free API Key.

Parameters

Api-Key

Required Parameters

POST

/watermarked-pdf

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" \
  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" \
  

Response

The response for your API Call will display here.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.

Build your solution

You have document processing problems, we have Solutions. Explore the many ways pdfRest can align your documents with your business objectives.

Browse all Solutions

Access PDF Processing Power with AI Magic

Integrate pdfRest with Microsoft Power Automate

Integrate PDF API Tools with Salesforce Apex Code

Control your Backend with pdfRest API Toolkit Self-Hosted

Secure PDF Documents with Protected Watermarks

A copyright mark is applied to a PDF document to protect a person's original ideas and creative designs

Preserve Copyright with PDF Watermarking

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.

Check out other videos

Start from Code Examples

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
Choose your programming language
Copy and paste the code to your project
Update Api-Key field with your unique API Key
Update file with the local path to your input
Run this code to send an API Call

See more code examples in our
GitHub repository

Try pdfRest with just a few clicks
Download our Postman Collection

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"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"

Need more help?

Start with a Tutorial for step-by-step guidance

How to Watermark PDF in .NET with C#

How to Watermark PDF with cURL

How to Watermark PDF with Java

How to Watermark PDF with JavaScript in NodeJS

How to Watermark PDF with PHP

How to Watermark PDF with Python

1 of 1 pages (6 items)

Customize Your Solution

file

The file parameter allows you to select a local file to be uploaded to pdfRest’s processing server.

The id parameter allows you to submit a resource ID generated by one of our API Tools. Each of our API Tools assigns a unique resource ID to your output file(s), allowing you to chain requests together without having to download intermediate files between requests.

For example, you can submit the output ID you receive from our Convert to PDF tool to watermark your new PDF document.

watermark_text

The watermark_text parameter lets you submit text to add as a watermark into your document.

The following parameters allow you to further adjust your text watermark:

font - set the font of your text watermark
text_size - set the font size
text_color_rgb or text_color_cmyk - set text color
opacity - set text opacity
x and y - horizontal and vertical offset, respectively
rotation - apply rotation to your text watermark

watermark_file

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

watermark_file_id

The watermark_file_id parameter allows you to submit a resource ID generated by one of our API Tools. The file associated with the resource ID will be applied to your input document as a PDF watermark.

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

text_size

The text_size parameter lets you specify the font size of a text watermark from 5 to 100.

output

The output parameter lets you set a filename (without extension) for your watermarked PDF.

font

The font parameter lets you set the font of your text watermark.

See our Font List for a complete list of fonts supported by pdfRest.

text_color_rgb

The text_color_rgb parameter lets you specify a color for your text watermark using the RGB color model.

Cannot be combined with the text_color_cmyk parameter.

text_color_cmyk

The text_color_cmyk lets you select a color for your text watermark using the CMYK color model.

Cannot be combined with the text_color_rgb parameter.

watermark_file_scale

The watermark_file_scale parameter lets you resize the content of a PDF watermark file.

opacity

The opacity parameter lets you set the opacity of your text or file watermark using a decimal value from 0.0 (fully transparent) to 1.0 (fully opaque).

The x parameter lets you set a horizontal offset from the center of the page for your watermark. Offset values use PDF units (72 units = 1 inch).

The y parameter lets you set a vertical offset from the center of the page for your watermark. Offset values use PDF units (72 units = 1 inch).

rotation

The rotation parameter lets you apply a rotation (in degrees) to your text or file watermark.

See Documentation

Generate a self-service API Key now!

Create your FREE API Key to start processing PDFs in seconds, only possible with pdfRest.

Compare Plans