---
title: ".NET Core API for adding watermarks to documents"
canonical_url: "https://www.nutrient.io/guides/document-converter/document-converter-services/watermark/dotnet-core/"
md_url: "https://www.nutrient.io/guides/document-converter/document-converter-services/watermark/dotnet-core.md"
last_updated: "2026-06-19T09:21:00.213Z"
description: "Add dynamic watermarks to PDF and Office files easily with our .NET Core API. Start your free trial today for seamless integration."
---

# Add watermarks to PDFs and Office files

### Online

[Online](https://www.nutrient.io/guides/document-converter/document-converter-services/watermark/dotnet-core.md)

### On-Premises

[On-Premises](https://www.nutrient.io/guides/document-converter/document-converter-services/watermark/dotnet-core-server.md)

Add text and image watermarks to PDF or Office files through our REST API. Dynamically add dates, times, and page numbers to the header and footer of your documents. Insert lines, rectangles, ellipses, barcodes, RTF files, images, and PDFs into your document. Apply multiple watermarks to the same page or to a range of pages (odd, even, portrait, or landscape). No server setup is required — simply start your free trial or sign up for an account to integrate watermarking capabilities into your application.

## Code Samples: Adding Watermarks Using.NET Core

Explore our code samples to learn how you can add watermarks to documents in your application or workflow. Or [contact us](https://www.nutrient.io/contact-sales) to explore other solutions!

1. [Add Watermarks to PDFs in.NET Core](https://github.com/Muhimbi/PDF-Converter-Services-Online/tree/master/clients/v1/dotnetcore/samples/watermarking)

2. [Add Watermarks to Office Documents in.NET Core](https://github.com/Muhimbi/PDF-Converter-Services-Online/tree/master/clients/v1/dotnetcore/samples/watermarking_office_document)

---

## Related pages

- [C# Watermark Server](/guides/document-converter/document-converter-services/watermark/csharp-server.md)
- [Add watermarks to documents with C#](/guides/document-converter/document-converter-services/watermark/csharp.md)
- [Java Watermark Server](/guides/document-converter/document-converter-services/watermark/java-server.md)
- [PDF Watermark API](/guides/document-converter/document-converter-services/watermark.md)
- [.NET Core Watermark Server](/guides/document-converter/document-converter-services/watermark/dotnet-core-server.md)
- [Add watermarks to PDFs using PHP API](/guides/document-converter/document-converter-services/watermark/php.md)
- [Add watermarks to your documents](/guides/document-converter/document-converter-services/watermark/java.md)
- [Add watermarks to your documents](/guides/document-converter/document-converter-services/watermark/javascript.md)