Digitally Sign PNG File Online via e-Signature App or using .NET

Develop powerful .NET based PNG document signing applications. Freely add digital signature into various documents including PNG files online via app with instant download.

PNG Signature via Python PNG Signature via Java

Add Digital Signature into PNG Files Online using App

  1. Upload PNG files to sign digitally.
  2. Add text for signature or upload signature image.
  3. Click the “Sign” button.
  4. Download the signed PNG file.

Digitally Sign PNG File via .NET

  1. Load canvas and signature images using Image.Load
  2. Use the Graphics class to load the canvas object
  3. Call DrawImage method to draw the signature
  4. Save the signed PNG image

.NET Code : Add Digital Signature in PNG Files


Develop E-Signature Application using .NET

Need to develop .NET script or utility app to easily sign multiple PNG files electronically? With Aspose.Imaging for .NET , child API of Aspose.Total for .NET , any .NET developer can integrate the above API code to program eSigning app for signatures across documents. Powerful .NET library for document signing, supports many popular formats including PNG format.

PNG eSignature library for .NET

There are three alternative options to install “Aspose.Imaging for .NET” or “Aspose.Total for .NET” onto your system. Please choose one that resembles your needs and follow the step-by-step instructions:

System Requirements

Our product is fully cross-platform and supports all major .NET implementations following ‘.NET Standard 2.0’ specification:

  • Microsoft .NET Framework, starting from the earliest 2.0 version, and ending with the latest ‘.NET Framework 4.8’
  • .NET Core, starting from the earliest 2.0, and ending with the latest ‘.NET 6’
  • Mono >= 2.6.7

    As .NET code doesn’t rely on the underlying hardware or operating system, but only on a Virtual Machine, so you are free to develop any kind of software for Windows, macOS, Android, iOS and Linux. Just make sure you have installed the corresponding version of .NET Framework, .NET Core, Windows Azure, Mono or Xamarin.

    We recommend using Microsoft Visual Studio, Xamarin, and MonoDevelop IDE to create C#, F#, VB.NET applications.

    For more details please refer to Product Documentation .


  • Can I use above .NET code in my application?
    Yes, you are welcome to download this code. One can easily develop a professional solution to add digital signature in PNG file using .NET. Use Aspose PNG eSignature API to develop high-level, platform independent software in .NET.
  • Is this document digital signing App work only on Windows?
    You have the flexibility to initiate document signing from any device, irrespective of the operating system it runs on, whether it be Windows, Linux, Mac OS, or Android. All that's required is a contemporary web browser and an active internet connection.
  • Is it safe to use the online app to sign multiple PNG documents?
    Of course! The output files generated through our service will be securely and automatically removed from our servers within a 24-hour timeframe. As a result, the download links associated with these files will cease to be functional after this period.
  • What browser should to use App?
    You can use any modern web browser like Google Chrome, Firefox, Opera, or Safari for online PNG document compression.
  • How can I sign multiple PNG files?
    Start by uploading one or more files you want to sign. You can either drag and drop your PNG files or simply click inside the white area. Afterward, click the 'Sign' button, and our online esigning app will quickly process the uploaded files.
  • How long does it take to sign the PNG files?
    This e-signature application operates quickly, It may take a few seconds to upload the files and sign them.

Explore File eSignature Options with .NET

Sign BMP (Bitmap Image File)
Sign DOC (Microsoft Word Binary Format)
Sign DOCX (Office 2007+ Word Document)
Sign GIF (Graphical Interchange Format)
Sign JPEG (Joint Photographic Expert Group)
Sign ODP (OpenDocument Presentation Format)
Sign ODS (OpenDocument Spreadsheet)
Sign ODT (OpenDocument Text File Format)
Sign PDF (Portable Document Format)
Sign PNG (Portable Network Graphic)
Sign PPT (PowerPoint Presentation)
Sign PPTX (Open XML presentation Format)
Sign TIFF (Tagged Image File Format)
Sign XLS (Microsoft Excel Binary Format)
Sign XLSX (Open XML Workbook)