Add Watermarks to Documents Using C#

Adding watermarks with 'Wordize for .NET' is simple and efficient. Whether you need to protect sensitive materials, add brand logos to business documents, or mark draft versions of contracts, Wordize simplifies watermarking any document. The C# API allows applying both text and image watermarks with full control over positioning, transparency, rotation angles, and formatting. Wordize is the ideal tool for automating watermark workflows in your .NET applications. Enhance document security, strengthen corporate branding, and streamline document processes with our C# API.

Key Features

Custom text watermarks with font, size, color, and transparency control
Image watermark insertion from various formats with automatic scaling
Application to specific pages or entire documents
Precise control over placement, rotation, and layering order
Support for DOCX, PDF, RTF, HTML and other formats

Practical Applications

Legal Industry: Clear marking of confidential docs and drafts
Corporate Branding: Embed company logos in official documents
Publishing: "Draft", "Confidential", or "Under Review" stamps
Education: Copyright protection for course materials and exams

Advanced customization options let developers adapt watermarks to specific needs, such as adjusting transparency for optimal readability while maintaining visibility. Test our product capabilities in the online demo - upload documents, configure watermark settings, and download watermarked files instantly.

Run code

Upload your document

Text of the watermark

Select the target format from the list

 
using Wordize.Watermarking;

Watermarker.SetText("Input.docx", "Output.pdf", "Text");

										using Wordize.Watermarking;

Watermarker.SetText("Input.docx", "Output.pdf", "Text");

										using Wordize.Watermarking;
using Wordize.Saving;

var imageStreams = Watermarker.SetWatermarkToImages("Input.docx", new ImageSaveOptions(SaveFormat.Pdf), "Text");

foreach (var (stream, page) in imageStreams.Select((s, i) => (s, i)))
{
    using var _ = stream;
    stream.Position = 0;
    
    using var file = File.Create($"Output_{page + 1}.pdf");
    stream.CopyTo(file);
}

using Wordize.Watermarking;

Watermarker.SetImage("Input.docx", "Output.pdf", "Watermark.jpg");

										using Wordize.Watermarking;

Watermarker.SetImage("Input.docx", "Output.pdf", "Watermark.jpg");

										using Wordize.Watermarking;
using Wordize.Saving;

byte[] watermarkImageBytes = File.ReadAllBytes("Watermark.jpg");
var imageStreams = Watermarker.SetWatermarkToImages("Input.docx", new ImageSaveOptions(SaveFormat.Pdf), watermarkImageBytes);

foreach (var (stream, page) in imageStreams.Select((s, i) => (s, i)))
{
    using var _ = stream;
    stream.Position = 0;
    
    using var file = File.Create($"Output_{page + 1}.pdf");
    stream.CopyTo(file);
}

				Run code

How to Watermark Documents in C#

Install Wordize for .NET
Add library reference to your project