Aspose.PDF  Product Family

PDF Document E-Signature Solution

Digitally sign PDF documents with free cross-platform Apps and APIs.

How to add Digitally Sign to PDF File

In order to add sign in PDF file, we’ll use Aspose.PDF API which is a feature-rich, powerful and easy to use document manipulation API. Open NuGet package manager, search for Aspose.PDF and install. You may also use the following command from the Package Manager Console. When signing a PDF document using a signature, you basically confirm its contents “as is”. Consequently, any other changes made afterward invalidate the signature and thus, you would know if the document was altered.

High Code APIs to Add E-Signatures from Document

Native APIs to e-sign PDF files using .NET, .NET Core, Xamarin, Java, C++ & Android

You can use following classed and method for PDF signing

  1. Class DocMDPSignature.
  2. Enumeration DocMDPAccessPermissions.
  3. Property IsCertified in PdfFileSignature class.


Sign PDF with digital signatures.

   var esign_doc = new Document("My File.pdf");
    var page = esign_doc.PdfDocument.Pages[1];
    // Create text stamp
    TextStamp textStamp = new TextStamp(getFormattedText("digital signature text"));
    // Set whether stamp is background
    // textStamp.Background = true;
    textStamp.HorizontalAlignment = HorizontalAlignment.Right;
    textStamp.VerticalAlignment = VerticalAlignment.Bottom;
    textStamp.TextAlignment = HorizontalAlignment.Center;
    textStamp.TextState.Font = FontRepository.FindFont("Arial");
    textStamp.TextState.FontSize = 50;
    textStamp.Width = page.PageInfo.Width / 3;
    textStamp.TextState.ForegroundColor = Color.FromRgb(System.Drawing.Color.Aqua);

    esign_doc.Save("esignedFile.pdf", SaveFormat.Pdf);

About Aspose.PDF API

Aspose.PDF API can be used for PDF document manipulation and parsing within applications. One can create, modify, compress, secure, print or save PDF to TXT, HTML, PCL, XFA, XML, XPS, EPUB, TEX, Images and more formats. Aspose.PDF is a standalone API and it does not depend on any software including Adobe Acrobat.

Online PDF eSignature Live Demos

e-Sign PDF documents right now by visiting our Live Demos website. The live demo has the following benefits.

  No need to download or setup anything
  No need to write any code
  Just upload your PDF file
  It will be electronically signed instantly