Paint.Net is a free and open source raster graphics editor program for Microsoft Windows. Paint.NET was originally created by Rick Brewster as a Washington State University student project, and has evolved from a simple replacement for the Microsoft Paint program into a fairly powerful yet easy to use image and photo editor tool. Paint.NET uses an innovative user interface with a tabbed document interface and support for layers, unlimited undo, special effects, and a wide variety of useful and powerful tools. The program is perfectly suited for tasks such as photo retouching, image composition, and graphic design.

Paint.NET features include simple one-click auto-leveling and color correction, automatic inpainting (fills in gaps in an image caused by removing objects), support for layer styles, advanced selection tools, support for plugins, and more.