Blender Windows, Mac, Linux
By Blender
For Everybody

Blender is the open source software for 3D modeling, animation, rendering, post-production, interactive creation and playback.

GIMP Windows, Mac, Linux
For Everybody

GIMP is an acronym for GNU Image Manipulation Program. It is a freely distributed program for such tasks as photo retouching, image composition and image authoring. The terms of usage and rules about copying are clearly listed in the GNU General Public License.

 For additional information, please refer to: GIMP: LSU Overview.

imgSeek Windows, Mac, Linux
By imgSeek
For Everybody

imgSeek is a photo collection manager and viewer with content-based search and many other features. The query is expressed either as a rough sketch painted by the user or as another image you supply (or an image in your collection).

For additional information, please refer to: imgSeek: LSU Overview.

Inkscape Windows, Mac, Linux
By Inkscape
For Everybody

Inkscape is an Open Source vector graphics editor, with capabilities similar to Illustrator, Freehand, CorelDraw, or Xara X using the W3C standard Scalable Vector Graphics (SVG) file format.

For additional information, please refer to: Inkscape: LSU Overview.

Krita Studio
By Krita
For Everybody

Krita Studio is the powerful painting application for professional artists, VFX and game studios. The uniquely innovative brush engines, the intuitive and fun interface and adherence to industry standards for pipeline integration, guarantee that Krita Studio supports your workflow and helps you get the most out of your ideas. It is a good alternative if you want photoshop but can't afford it. It is open source and seems aimed at game makers and artists.

Paint.NET Windows
By Paint.NET
For Everybody

Paint.NET is image and photo manipulation software. It supports layers, unlimited undo, special effects, and a wide variety of useful and powerful tools.

Pixia Windows
By Pixia
For Everybody

Pixia is a free painting tool made exclusively for full color graphics. The original application was Japanese, but this English version is now available.

For Windows 7-8.1 use the 32-bit version. For 8.1 and above, use the 64-bit version. 

By Seashore
For Everybody

Seashore is an open source image editor for Cocoa. It features gradients, textures and anti-aliasing for both text and brush strokes. It supports multiple layers and alpha channel editing. It is based on GIMP and uses the same native file format.