Paint.NET is free image editing and photo manipulation software designed to be used on computers that run Windows. It supports layers, unlimited undo, special effects, and a wide variety of useful and powerful tools.

It started development as an undergraduate college senior design project mentored by Microsoft, and is currently being maintained by some of the alumni that originally worked on it. Originally intended as a free replacement for the MS Paint software that comes with Windows, it has grown into a powerful yet simple tool for photo and image editing.

The programming language used to create Paint.NET is C#, with a small amount of C++ for installation and shell-integration related functionality.

What's new in Paint.NET v3.0?

• Simple and intuitive tab-based multi-document user interface
     
  
• Now available in 8 languages: English, Chinese (Simplified), French, German, Japanese, Korean, Portuguese (Brazil), and Spanish
     
  
• Interactive Gradient Tool that makes it very easy to draw and then fine-tune placement and coloring of a gradient
     
  
• User-definable color palette (as opposed to just the color wheel)
     
  
• New effects: Clouds, Median, Unfocus, Outline, and an improved Sharpen
     
  
• More intuitive and more powerful toolbar
     
  
• Generally improved and cleaner user interface
     
  
• History files are now compressed to save disk space, reduce disk activity, and improve performance
     
  
• "Merge Down" layer command
  

Please note that Windows 2000 is no longer supported. Paint.NET v3.0 will not install unless your operating system is Windows XP SP2 or newer. If you would like to use Paint.NET on Windows 2000, you will need to install Paint.NET v2.72 or earlier.