Open-Source Software list | Free CGI Software list

Discover a treasure trove of open-source software and free CGI tools in our comprehensive list. Unleash your creativity, boost productivity, and save costs with these powerful resources for CGI enthusiasts and professionals alike. Embrace the world of limitless possibilities as we highlight top-notch solutions for your CGI projects.

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3D modeling, animation, and rendering

Blender (complete 3D animation, fx, simulation, sculpting, texturing, rendering, etc)
http://www.blender.org/

SketchUp
http://sketchup.google.com/

fSpy (camera alignment)
https://fspy.io/

Clara.io (web based 3D)
https://clara.io/

Form Z Free
http://www.formz.com/products/formzfree.html

Gaffer (Lighting, shading, and compositing, Linux and Mac only)
https://github.com/GafferHQ/gaffer

Open 3D Model Viewer (Windows only, model viewer only)
http://www.open3mod.com/

Equinox 3D (Mac and Linux only)
http://www.equinox3d.com/index.html

Gloss3D (Linux only)
http://sourceforge.net/projects/gloss3d/files/

Dust3D (modeling, Windows and Mac, build your own for Linux)
https://github.com/huxingyi/dust3d

Mach Studio Pro (is this still available? - not sure)
http://www.studiogpu.com/machstudio

MakeHuman (creating human models)
http://www.makehuman.org/

ManuelBastioniLab
http://www.manuelbastioni.com/

SculptGL (Web-based sculpting)
http://stephaneginier.com/sculptgl/

Werkkzeug 4 CE (Windows only)
http://werkkzeug4ce.blogspot.com/

Bryce Personal Learning Edition (Windows and Mac only)
http://www.daz3d.com/i/products/bryce/download?

Sculptris (sculpting only, now owned by Zbrush, but still free)
http://www.sculptris.com/

Dilay (sculpting only, Windows and Linux only)
http://abau.org/dilay/index.html

Neobarok (sculpting, no download links yet, just demos)
https://neobarok.wordpress.com/

MeshMolder (sculpting, beta, Windows only)
http://www.meshmolder.com/index.html

Smoothie-3D (sketch-based, online)
http://www.smoothie-3d.com/

Shapeshop (sketch-based 3D)
http://www.shapeshop3d.com/

MeshMixer (3D mesh editor and sculpting)
http://www.meshmixer.com/

Shadow’s Spider (very basic, written by one person)
https://github.com/bergjones/Shadows_Spider

Sketch-Based Experimental modeling tool
http://www.gunayorbay.com/tutorial/

I Love Sketch (sketch-based modeling, is this released? Not sure.
http://www.dgp.toronto.edu/~shbae/ilovesketch.htm

Terragen (natural landscapes and atmospheres)
http://www.planetside.co.uk/

Meshlab (processing and cleaning up of dense 3D meshes)
http://meshlab.sourceforge.net/

Netfabb Studio Basic (processing and cleaning up of dense 3D meshes, prep for STL printing)
http://www.netfabb.com/basic.php

Slic3r (G-code generator for 3d printers)
http://slic3r.org/

TinkerCAD (browser-based, good for 3d printing)
https://tinkercad.com/

Nervous System Tools (browser-based, organic cellular forms, good for 3d printing)
http://n-e-r-v-o-u-s.com/tools/

Tree it (maybe Windows only)
http://www.evolved-software.com/treeit/treeit

Arbaro (tree & plant generator, requires Java)
http://arbaro.sourceforge.net/

ngPlant (tree & plant generator, Windows and Mac only)
http://ngplant.sourceforge.net/

PlantStudio (tree & plant generator, Windows only)
http://www.kurtz-fernhout.com/summary_plantstudio.html

TerrSculptor (Windows only, only free while in beta)
http://www.lilchips.com/hmes.asp

Suicidator City Generator (for Blender)
http://arnaud.ile.nc/sce/

CrackArt (Texture painting and materials, Windows only)
http://crackart.org/

Ivy Generator
http://graphics.uni-konstanz.de/~luft/ivy_generator/

http://vivec3d.com/3d-ivy-generator-2012/ (multi-core version, much faster)

Ayam (NURBS modeling only)
http://ayam.sourceforge.net/ayam.html

Nurbana (NURBS modeling only, Linux only?)
http://sourceforge.net/projects/nurbana/

LEGO Digital Designer (Windows and Mac only)
http://ldd.lego.com/

DAZ Studio
http://www.daz3d.com/i/software/daz_studio3?_m=d

L3DT (Terrain maps and textures, Windows only)
http://www.bundysoft.com/L3DT/

Wilbur (Terrain creation, Windows only)
http://www.ridgenet.net/~jslayton/wilbur.html

ParaView (data analysis and visualization)
http://www.paraview.org/

LightRay3D (Windows only)
http://www.sxcreations.com/lr3d/lightray3d.php

3DCrafter (Basic version, Windows only)
http://www.amabilis.com/products.htm

Truespace (discontinued in 2008)
http://download.cnet.com/TrueSpace/3000-6677_4-10187286.html

Lithosphere (terrain generation, maybe abandoned)
http://lithosphere.codeflow.org/

Breeze Designer (Windows only)
http://www.breezedesigner.com/

Model Magic 3D (Windows only)
http://www.imagewaredev.com/

ArtMatic 5 and ArtMatic Voyager (Mac only)
http://uisoftware.com/artmatic/indexAMVY.php

Moray (modeller for POV-Ray)
http://www.stmuc.com/moray/index.html

Anim8or
http://www.anim8or.com/main/index.html

MarbleCLAY
http://homepage3.nifty.com/escargot/MCLFrm.html

Art of Illusion
http://www.artofillusion.org/index

Deled CE
http://www.delgine.com

K-3d
http://www.k-3d.org/

Moonlight 3D
http://www.moonlight3d.eu/cms/index.php/about

SmoothTeddy
http://www-ui.is.s.u-tokyo.ac.jp/~takeo/java/smoothteddy/index.html

Wings 3D
http://www.wings3d.com/

Dynamo BIM (Graphical programming interface for building information, Windows only)
http://dynamobim.org/

kHED (modeling only, Windows only)
http://khed.glsl.ru/index.php?page=home

Open Dental CAD (designing crowns and related dentistry, for Blender)
http://opendentalcad.com/

FaceGen (only the modeler is free, Windows only)
http://www.facegen.com

Scannerkiller (online photo modeling service) NO LONGER AVAILABLE
http://www.xyzrgb.com/scannerkiller

Make 3D (Cornell University project to create 3D model from single photo)
http://make3d.cs.cornell.edu/

Metasequoia (Windows only)
http://metaseq.net/english/

TopMod (Manifold Mesh modeling, Windows only)
http://www.viz.tamu.edu/faculty/ergun/research/topology/download.html

Sweet Home 3D (interior design and layout)
http://www.sweethome3d.com

BubblEd (sphere modeling, Windows only)
http://www.quelsolaar.com/bubbled/index.html

Qoob (small model creation, Windows only)
http://qoob.weebly.com

Balancer Lite (mesh optimizer, Windows, and Mac only)
http://www.atangeo.com/download

CloudCompare (mesh cleanup, Windows, and Linux only)
http://www.danielgm.net/cc/

Pointshop 3D (discontinued in 2006)
http://graphics.ethz.ch/pointshop3d/index.html

3D Crafter (Windows only)
http://www.amabilis.com/products.htm

Loq Airou (model sketcher)
http://quelsolaar.com/loq_airou/

Photogrammetry (modeling from photos)

Mushroom (Open source photo modeling)
https://github.com/alicevision/meshroom
https://alicevision.github.io/

Python Photogrammetry Toolbox (Windows and Linux only)
http://184.106.205.13/arcteam/ppt.php

Clustering Views for Multi-view Stereo (CMVS) (Photomodelling, Windows and Linux only, I think)
http://www.di.ens.fr/cmvs/

VisualSFM (Photomodelling)
http://ccwu.me/vsfm/

Regard3D (Photomodelling)
http://www.regard3d.org/

Smart3DCapture (Photomodelling, Windows only)
https://community.acute3d.com/smart3dcapture-free-edition

Insight3D (Photomodelling, Windows, and Linux only)
http://insight3d.sourceforge.net/

Open Source photogrammetry
http://opensourcephotogrammetry.blogspot.com/

Stereo (Photomodelling, a student project from 1996-97)
http://stereo.sourceforge.net/

Rendering engines

Appleseed (renderer only)
http://appleseedhq.net/

Kerkythea (renderer only)
http://www.kerkythea.net/joomla/

Loki Render (render farm for Blender)
http://loki-render.sourceforge.net/index.php/Main_Page

Jot (standalone non-photorealistic renderer only)
http://jot.cs.princeton.edu/

Mitsuba (renderer only)
http://www.mitsuba-renderer.org/index.html

Fujiyama (renderer only)
http://fujiyama-renderer.com/

Corona Renderer (renderer only)
https://corona-renderer.com/

Yafray (renderer only, for Blender)
http://www.yafaray.org/

POV Ray (renderer only)
http://www.povray.org/

Pixie (Renderman rendering)
http://www.renderpixie.com/

Other links for using Renderman with Blender
http://www.blendertorenderman.org/p/links.html

Ogre (renderer only)
http://www.ogre3d.org/

Horde3D (rendering engine)
http://horde3d.org

LuxRender (renderer only, for most 3D programs)
http://www.luxrender.net/en_GB/index

Video editing

Lightworks
http://www.lwks.com/

Blender (complete non-linear editor)
http://www.blender.org/

Shotcut
http://www.shotcutapp.com/
http://shotcutapp.blogspot.dk/

DaVinci Resolve Free
https://www.blackmagicdesign.com/products/davinciresolve

Avid Media Composer First
http://www.avid.com/media-composer-first/

OpenShot
http://www.openshot.org/

ClipChamp Create (browser-based editing)
https://clipchamp.com/en/products/create

VideoLAN Movie Creator
http://trac.videolan.org/vlmc/

ZS4 Video Editor
http://www.zs4.net/

Kdenlive (Linux, beta on Windows & Mac)
http://www.kdenlive.org

VSDC Video Editor
http://www.videosoftdev.com/free-video-editor

VirtualDub (also captures video)
http://www.virtualdub.org/

MPEG Streamclip
http://www.squared5.com/

Avidemux
http://fixounet.free.fr/avidemux/

Wax (Windows only)
http://www.debugmode.com/wax/

Windows Movie Maker (Windows only)
http://explore.live.com/windows-live-movie-maker?os=other

Flowblade (Linux only)
https://jliljebl.github.io/flowblade/index.html
http://code.google.com/p/flowblade/

Cinelerra (Linux only)
http://cinelerra.org/

Open Movie Editor (Linux only)
http://www.openmovieeditor.org/

HyperEngine-AV
http://sourceforge.net/projects/hyperengine/files/

VideoSpin (Windows only)
http://videospin.en.softonic.com/

Video Software Development Company (Windows only, might install adware, check reviews)
http://www.videosoftdev.com/

Vivia (Linux and Windows only, not updated since 2007)
http://vivia-video.org/

PiTiVi (Linux only)
http://www.pitivi.org/

Compositing

Blender (node-based compositing)
http://www.blender.org/

Natron (node-based compositing)
https://natron.inria.fr/

Blackmagic Fusion (node-based compositing)
https://www.blackmagicdesign.com/products/fusion

Phantom2D Motion Graphics (Linux only)
https://code.google.com/p/phantom2d/

Gaffer (Lighting, shading, and compositing, Linux and Mac only)
http://imageengine.github.io/gaffer/index.html

ButtleOFX (Linux only, is it still in development?)
http://buttleofx.wordpress.com/

Synapse (Windows XP and Linux only, not updated since 2011)
http://code.google.com/p/vexx/

Ramen (Linux only, not updated since 2011)
http://ramencomp.blogspot.com/

Wax (Windows only, not updated since who knows when!)
http://www.debugmode.com/wax/

Mewa Film (Windows only)
http://mewafilm.blogspot.com/

ZS4 Video Editor
http://www.zs4.net/

CineGobs (keying software only, Windows only)
http://cinegobs.com

VirtualDub Deshaker (stabilizing shaky footage, Plugin for VirtualDub)
http://www.guthspot.se/video/deshaker.htm

Cinepaint (multi-frame painting & retouching, Linux and Mac OS only)
http://www.cinepaint.org/more/

Moviepaint (multi-frame painting & retouching, not sure of OS)
http://sourceforge.net/projects/moviepaint/

Jahshaka (v2.0 was real and very buggy, v3.0 was rumored to be a scam but now seems to be being worked on)
http://www.jahshaka.com/

Retiming Footage

Slo-mo video (Linux and Windows only)
http://slowmovideo.granjow.net/
http://slowmovideo.granjow.net/builds.php#h3_Windowsexecutables (Windows version)

CAD (Computer-Aided Design)

NanoCAD
http://nanocad.com/

DraftSight
http://www.3ds.com/products/draftsight/overview/

LibreCAD
http://librecad.org/cms/home.html

QCAD (Community Edition)
http://www.ribbonsoft.com/qcad.html

FreeCAD France
http://www.freecad-france.com/

FreeCAD
http://www.freecadweb.org/

Ayam
http://ayam.sourceforge.net/

gCAD 3D
http://www.gcad3

Doubled.org/CAD XT
http://www.doublecad.com/Products/DoubleCADXTv3/tabid/1100/Default.aspx

BRL-CAD
http://brlcad.org/

OpenSCAD (model by programming)
http://www.openscad.org/

Wildcat-CAD
http://code.google.com/p/wildcat-cad/

CADemia
http://www.cademia.org/frontend/index.php?sub=29&ses_id=d47a993c0b9558b68f9f89c122d45098

PythonCAD
http://sourceforge.net/projects/pythoncad/

SolveSapce (Windows only)
http://solvespace.com/index.pl

HeeksCAD (Windows and Linux only)
http://code.google.com/p/heekscad/

Blender CAD edition (old version)
http://www.cad4arch.com/blenderCADedition/index.htm

Vectorworks 2012 Viewer
http://www.vectorworks.net/downloads/fundamentals/index.php

Various Mechanical Engineering software
http://www.freebyte.com/cad/cad.htm#2D3DCADSystems

Video players and Viewers (3d models, etc)

VLC
http://www.videolan.org/vlc/

MPC-HC (Possible better alternative to VLC, better scrubbing?)
https://mpc-hc.org/

JefeCheck (frame sequences as well as movies)
http://jefecheck.jefecorp.com/index.html

DJV Imaging (frame sequences as well as movies)
http://djv.sourceforge.net/
http://djv.sourceforge.net/djvHelp.html

POT Player (Windows only)
https://potplayer.daum.net/

MPV player
https://mpv.io/

SCRATCH Play (Windows and Mac only)
http://www.assimilateinc.com/products/scratch-play

SqCheck (not developed since 2011)
http://sqview.sourceforge.net/index.html

Bview (Linux and Mac only)
http://bufsoftware.com/products/bview/

Bino (supports stereoscopic 3D viewing)
http://bino3d.org/

Free Image Sequence Player (for frame sequences)
http://mateuszstaniszew.pl/index.php?m=3&p=4

Duke (Open Mikros Image)
http://opensource.mikrosimage.eu/duke.html

Clockstone FBX Viewer (for viewing 3D files)
http://fbx.clockstone.com/index.html

GLC Players (OBJ viewer)
http://www.glc-player.net

FBX Review
http://area.autodesk.com/products/features/fbx

Miro (seems like iTunes)
http://www.getmiro.com/

mrViewer (Linux and Windows only)
http://sourceforge.net/projects/mrviewer/

SUPER (Simplified Universal Player Encoder & Renderer) (Windows only)
http://www.erightsoft.com/SUPER.html

FISP (Free Image Sequence Player) (Windows only)
http://mateuszstaniszew.pl/index.php?menu=04&other=04

Video transcoding and compression

Cliptoolz Convert (Windows only?)
http://www.cliptoolz.com/

MakeMKV (also rips blu rays and DVDs)
http://www.makemkv.com/

MediaCoder
http://www.mediacoderhq.com/

Handbrake
http://handbrake.fr/

MPEG Streamclip
http://www.squared5.com/

Format Factory
http://formatfactory.org/

Avanti/Avisynth/FFmpeg (Windows only)
http://avanti.arrozcru.com/

Arista Transcoder
http://www.transcoder.org/

Video Software Development Company (Windows only, might install adware, check reviews)
http://www.videosoftdev.com/

SUPER (Simplified Universal Player Encoder & Renderer) (Windows only)
http://www.erightsoft.com/SUPER.html

Image editing and photo retouching

GIMP
http://www.gimp.org/

Nodewerk (node based photo editing, requires Adobe Air)
http://nodewerk.com/

Krita (Linux and Windows only, Mac is experimental)
http://www.krita.org/

AzPainter
https://frankqbe.deviantart.com/art/AzPainter-212-English-Version-Download-488404806

LightZone (similar to Adobe Lightroom)
http://www.lightzoneproject.org/

Fotografix (ideal for netbooks, Windows only)
http://lmadhavan.com/software/fotografix/

FireAlpaca (Windows and Mac only)
http://firealpaca.com/

Cinepaint (for image sequences, too)
http://www.cinepaint.org/

MoviePaint (for image sequences, too)
http://sourceforge.net/projects/moviepaint/

Pixel
http://www.kanzelsberger.com/pixel/

Pixlr (Windows and Mac only)
https://pixlr.com/desktop

Photobie (Windows only)
http://www.photobie.com/

Photoscape (Windows only)
http://www.photoscape.org/ps/main/index.php

PixBuilder Studio (Windows only)
http://www.wnsoft.com/pixbuilder/

StylePix (Windows only)
http://hornil.com/en/products/stylepix/

Chasys Draw IES (Windows only)
http://www.chachaslab.com/chasys_draw_ies.php

Paint.NET (Windows only)
http://www.getpaint.net/

Pinta
http://pinta-project.com/

Picasa
http://picasa.google.com/

Microsoft Image Composite Editor (Windows only, stitcher)
https://www.microsoft.com/en-us/research/product/computational-photography-applications/image-composite-editor/

Hugin (panoramic photo stitcher)
http://hugin.sourceforge.net/

Photoscape (Windows only)
http://www.photoscape.org

JTL Ultimate Paint (32 bit Windows only, trial is fully functional)
http://www.ultimatepaint.com/

Whyteboard (basic painting & annotating PDFs, Windows and Linux only)
http://whyteboard.org/

Photivo (RAW processing and digital darkroom)
http://code.google.com/p/photivo/

RAW Therapee (RAW processing and digital darkroom)
http://rawtherapee.com/

DigiKam (RAW processing and digital darkroom)
http://www.digikam.org/

Blue Marine (RAW processing and digital darkroom)
http://bluemarine.tidalwave.it//

Darktable (RAW processing and digital darkroom, Linux and Mac only)
http://darktable.sourceforge.net

RAW Studio (RAW processing, Linux only)
http://rawstudio.org/

Flaming Pear Free Plugins (Not all silly, some useful ones)
http://flamingpear.com/goodies.html

Easy Green Screen (free greenscreen plug-in for Photoshop)
http://www.photoshopgreenscreen.com/

Zebratrace (woodcut effect, Windows and Linux only)
http://maxim-s-barabash.github.io/ZebraTrace/

Dydelf (posterized graphics tool, Windows only)
http://dydelf.republika.pl/index.html

Browser-based Image editing, painting, and photo retouching No Installation works from anywhere with an internet connection!)

SumoPaint
http://www.sumopaint.com

ToolPic (Photoshop Online)
http://www.toolpic.com/

Adobe Photoshop Express
http://www.photoshop.com/tools/overview

Photopea
http://www.photopea.com/

Pixlr
http://www.pixlr.com

Rebelle (Experimental, watercolor painting)
http://www.escapemotions.com/experiments/rebelle/

Splashup
http://www.splashup.com/

Muro (deviantart's paint program)
http://muro.deviantart.com/

FlauntR
http://www.flauntr.com/

FotoFlexer
http://fotoflexer.com/

GMIC Greyc’s Magic for Image Computing (online filters and effects)
https://gmicol.greyc.fr/

Browser-based Video Editing(No Installation works from anywhere with an internet connection!)

WeVideo
https://www.wevideo.com/

YouTube Video Editor
https://www.youtube.com/editor/

Video Toolbox
http://www.videotoolbox.com/

JW Player Editor
http://jwplayer.mixmoov-studio.com/flex/jwplayer.html

FileLab Video Editor
https://www.filelab.com/video-editor

VideoPad Editor (Windows only)
http://www.nchsoftware.com/videopad/index.html

Browser-based 3D(No Installation works from anywhere with an internet connection!)

TinkerCAD (good for 3d printing)
https://tinkercad.com/

3D Tin
http://www.3dtin.com/

Shapesmith
http://shapesmith.net/

Smoothie-3D (sketch-based, online)
http://www.smoothie-3d.com/

SculptGL (Web-based sculpting)
http://stephaneginier.com/sculptgl/

ThreeNodes (node-based procedural engine)
http://idflood.github.io/ThreeNodes.js/public/

Sweet Home 3D (interior design and layout)
http://www.sweethome3d.com

Nervous System Tools (organic cellular forms, good for 3d printing)
http://n-e-r-v-o-u-s.com/tools/

P3D (viewing models only)
http://p3d.in/

3D Model Exchanging
OD_CopyPasteExternal
https://heimlich1024.github.io/OD_CopyPasteExternal/

Verse
http://quelsolaar.com/verse/index.html

Rigging

Mixamo Auto-rigger (free for characters under 10,000 triangles)
http://www.mixamo.com/c/auto-rigger

Caustics Pattern/Animation Generator

Kool Lite Tools Caustic Generator v1.4 (Windows only)
http://www.klitetools.com/comments.php?shownews=4130&catid=68

Caustics Generator
http://www.dualheights.se/caustics/

Procedural Texture Creation and Editing

NeoTextureEdit
http://neotextureedit.sourceforge.net/

MaPZone
http://www.mapzoneeditor.com/

tg (Texture Generator)
http://www.blackpawn.com/dev/tg.html

nMaker Tools (Windows only, maybe)
http://www.nmaker.com.br/index.html

NoiseLab
https://sites.google.com/site/noiselab15/

Substance Player (Windows and Mac only)
http://www.allegorithmic.com/products/player

Wood Workshop (Windows only)
http://www.spiralgraphics.biz/ww_overview.htm

Texture Ripper (extracting textures from photos)
http://myclone.wordpress.com/2010/06/13/textureripper/

Auto Normal maps, Ambient Occlusion, etc...

Materialize
http://boundingboxsoftware.com/materialize/

PixaFlux (Windows only)
http://pixaflux.com/index.php

https://blenderartists.org/forum/showthread.php?391893-PixaFlux-PBR-Texture-Composer-Open-Beta-Testing

NormalMap Generator (Windows and Linux only)
https://github.com/Theverat/NormalmapGenerator

MaPZone
http://www.mapzoneeditor.com/

Smart Normal - (browser-based, no installation)
http://www.smart-page.net/smartnormal/

SMAK - Super Model Army Knife (Windows only)
http://getsmak.net/

xNormal
http://www.xnormal.net/1.aspx

Crazy Bump
http://www.crazybump.com/

HDRI Software

HDR Shop (Version 1 only, Windows only)
http://www.hdrshop.com/

Luminance HDR
http://qtpfsgui.sourceforge.net/

FDR Tools Basic (Windos and Mac only)
http://fdrtools.com/fdrtools_basic_e.php

Essential HDR Community Edition (Windows only)
http://www.imagingluminary.com/Default.aspx

Picturenaut (Windows only)
http://www.hdrlabs.com/picturenaut/index.html

Smart IBL
http://www.hdrlabs.com/sibl/sibl-edit.html

http://www.hdrlabs.com/sibl/index.html

http://www.hdrlabs.com/picturenaut/index.html

3D Matchmoving

Blender (full 2d tracking, 3d camera solving, and set reconstruction)
http://www.blender.org/

Icarus
http://web.archive.org/web/20021203195907/aig.cs.man.ac.uk/icarus/index.php

Icarus training and links
http://www.colinlevy.com/tuts/IcarusTutorials/Icarus.php

Voodoo - Might be DEAD!
http://www.digilab.uni-hannover.de/docs/manual.html

ACTS: Automatic Camera Tracking System (Windows only)
http://zjucvg.net/acts/acts.html

Vector illustration

Inkscape
http://inkscape.org/

Browser-based Vector illustration(No Installation works from anywhere with an internet connection!)

SVG-edit
http://svg-edit.googlecode.com/svn/branches/2.6/editor/svg-editor.html

Janvas
http://www.janvas.com/

Chittram
http://www.chittram.com/

Fractal Generators

Qosmic
http://code.google.com/p/qosmic/

Apophysis
http://apophysis.org/

Apophysis 7x (improved version of Apophysis)
http://apophysis.xyrus-worx.org/

Mandelbulber
http://www.mandelbulber.com/

Oxidizer (Mac only)
http://oxidizer.sourceforge.net/Site/Oxidizer.html

Bitmap to Vector conversion

Autotrace Online
http://www.roitsystems.com/cgi-bin/autotrace/tracer.pl

2D animation

Pencil 2D
http://www.pencil2d.org/

Toonz (soon will be open-sourced)
http://www.toonzpremium.com/

Plastic Animation Paper
http://plasticanimationpaper.dk/

Synfig Studio (similar to Flash)
http://synfig.org

VPaint (still in development, very new)
http://vpaint.org/

Animata (similar to Flash, Windows and Mac only)
http://animata.kibu.hu

Giotto (similar to Flash, Windows only)
http://vectorian.com/giotto/

Creatoon (No longer being developed, Windows only)
http://www.creatoon.com/

KTooN (Linux only)
http://www.ktoon.net/portal/

Tupi (branched from KTooN, Linux and maybe Mac only)
http://www.maefloresta.com/portal/

Stop Motion Animation

Helium Frog Animator
http://www.heliumfrog.com/

qStopMotion
http://www.qstopmotion.org/

MonkeyJam
http://monkeyjam.org/

Sketching/Natural media/Art/Painting

MyPaint
http://mypaint.org/

Krita (Linux and Windows only, Mac is experimental)
http://www.krita.org/

openCanvas ( v1.1 only is free, I think Windows only)
http://wistinga.online.fr/opencanvas/

Paint Tool SAI
http://www.systemax.jp/en/sai/
http://detstwo.com/sai/ (English version)

SpeedyPainter (Windows only)
http://speedypainter.altervista.org/

Verve Painter (Fluid dynamics painting, Windows only)
http://www.taron.de/forum/

GIMP Paint Studio
http://code.google.com/p/gps-gimp-paint-studio/

Windows 7 Open Drawing Package (MyPaint, GIMP-Painter, and Alchemy)
http://vegeti.fr/index.php?option=com_content&view=article&id=59

Artrage 2 (Starter Edition)
http://www.artrage.com/artrage-demos.html

Artweaver (Windows only)
http://www.artweaver.de/

Autodesk Sketchbook Copic Edition (marker rendering)
http://copic.jp/sketchbook-ce.html

Creo Sketch
http://www.ptc.com/products/creo/sketch/

Audio

Audacity
http://www.audacityteam.org/

Ocenaudio
http://www.ocenaudio.com/

Qtractor
https://qtractor.sourceforge.io/

Ardour (Mac and Linux only)
http://www.ardour.org/

Linux Multimedia Studio (Linux and Windos only)
http://lmms.sourceforge.net/home.php

Smasher (Loop slicer and creation)
http://sourceforge.net/projects/smasher/

Sonic Visualizer (in-depth analyzing of audio files)
http://www.sonicvisualiser.org

Psycle Modular Music Creation Studio (Windows and Linux only)
http://sourceforge.net/projects/psycle/

Hydrogen Drum machine (Linux only)
http://www.hydrogen-music.org/hcms/

Open Octave Studio (Linux only)
http://www.openoctave.org/

Music Scoring

MuseScore (Windows only)
http://musescore.org/

Rosegarden
http://www.rosegardenmusic.com/

Browser-based Music Creation(No Installation works from anywhere with an internet connection!)

AudioSauna
http://www.audiosauna.com/

Video & Audio Conversions

Freemake (Windows only)
http://www.freemake.com/

Video Software Development Company (Windows only, might install adware, check reviews)
http://www.videosoftdev.com/

PhotoLapse 3 (JPGs to AVI, Windows only)
http://home.hccnet.nl/s.vd.palen/photolapse.html

SUPER (Simplified Universal Player Encoder & Renderer) (Windows only)
http://www.erightsoft.com/SUPER.html

Hamster Soft tools (Windows only, except for ZIP Archiver)
http://www.hamstersoft.com/

Screenwriting, pre-production, & texts

Trelby (Windows and Linux only, Mac coming soon, works with Final Draft formats)
http://www.trelby.org/

Celtx
http://www.celtx.com/

KIT Scenarist
https://kitscenarist.ru/en/index.html

Afterwriting (browser-based)
https://afterwriting.com/

WriterDuet (browser-based, collaborative, exports to all popular screenplay formats)
https://www.readthrough.com/writerduet#home

oStorybook (novel writing and outlining)
https://ostorybook.wordpress.com/

ScriptMaker (screenwriting)
https://scriptmaker.jaleco.com/

Slang (story development)
https://slang.en.softonic.com/

Microsoft Word Screenplay Template
http://office.microsoft.com/en-us/templates/screenplay-TC001018636.aspx

Screenplain (online text-to-screenplay convertor)
http://www.screenplain.com/

Page 2 Stage (Windows only)
http://www.page2stage.com/

Rough Draft (Windows only, no longer updated)
http://www.salsbury.f2s.com/rd.htm

Plotbot (Online only)
http://www.plotbot.com/

Five Sprockets (Online only)
http://www.fivesprockets.com

OpenOffice (full office suite)
http://www.openoffice.org/

OpenOffice Screenplay Template
http://extensions.openoffice.org/en/project/scr2

LibreOffice (full office suite)
http://www.libreoffice.org/

WPS Office
https://www.wps.com/office-free

ReadThrough (1-month trial, will read your script aloud)
http://www.readthrough.com/

Tomboy (note-taking & organizing)
http://projects.gnome.org/tomboy/index.html

KeepNote (note-taking & organizing)
http://keepnote.org/index.shtml

wikidPad (Wiki-like notebook)
http://wikidpad.sourceforge.net/

Keynote-NF (note-taking & organizing, Windows only)
http://code.google.com/p/keynote-nf/

Fountain (some kind of framework for text in screenplay format, I’m not sure)
http://fountain.io/

FreeMind (graphical layout and organization) (Java-based)
http://freemind.sourceforge.net/wiki/index.php/Main_Page

SimpleOCR (Optical Character Recognition)
http://www.simpleocr.com/

Scanning Software

VueScan
http://www.hamrick.com/

FreeKapture 2.0 (Windows Only)
http://www.freewarefiles.com/FreeKapture_program_32165.html

Web design

Kompozer
http://kompozer.net/

NetObjects Fusion Essentials
http://netobjects.com/html/essentials.html

Bluefish
http://bluefish.openoffice.nl/index.html

BlueGriffon
http://bluegriffon.org/

NVU
http://net2.com/nvu/

Desktop Publishing & Page Layout

Scribus
http://www.scribus.net/canvas/Scribus

PagePlus
http://www.serif.com/desktop-publishing-software/

Paper Craft Model Layout

Pepakura Designer 3
http://www.tamasoft.co.jp/pepakura-en/

Font creation

FontForge
http://fontforge.sourceforge.net/

Fontstruct
http://fontstruct.com/

Birdfont
http://birdfont.org/

PDF editing

PDFedit (might be Linux only)
http://sourceforge.net/projects/pdfedit/

PDF converting and altering
https://www.ps2pdf.com/

PDFforge
http://www.pdfforge.org/

PDFsam
http://www.pdfsam.org/

Ebook Management

Calibre
http://calibre-ebook.com/

Sigil (ebook editor)
https://github.com/Sigil-Ebook/Sigil

Novel writing

yWriter
http://www.spacejock.com/yWriter5.html

WriteWayPro
http://www.writewaypro.com/

Thumbnail Viewer

SageThumbs (Windows only)
https://code.google.com/p/sagethumbs/

Zip compression

7zip
http://www.7-zip.org/

Screen Recording & Capturing

Screencast-O-Matic (browser-based, no installation necessary!)
http://www.screencast-o-matic.com/

CamStudio
http://www.camstudio.org/

Open Broadcaster Software
http://obsproject.com/

AutoScreenRecorder 3.1
http://wisdom-soft.com/products/autoscreenrecorder_free.htm

PicPick
http://picpick.org

HyperCam v2 (Windows only)
http://www.hyperionics.com/hc/index.asp

Wink (Windows and Linux only)
http://www.debugmode.com/wink/

Render Queue Management

DrQueue
http://www.drqueue.org/cwebsite/

RenderChan
https://morevnaproject.org/renderchan/

Online Aspect Ratio Calculator

http://andrew.hedges.name/experiments/aspect_ratio/

Tracking Data Conversion between commercial Compositing programs

http://tracksperanto.guerilla-di.org/

Pattern Making for Clothing

Valentina
http://valentina-project.blogspot.ru/
https://bitbucket.org/dismine/valentina

Browser-based Flowchart creator

Gliffy
http://www.gliffy.com

Lucid Chart
https://www.lucidchart.com/pages/flow-chart

Image Viewer

Irfanview
http://www.irfanview.com/

FastStone
http://www.faststone.org/FSViewerDetail.htm

Matcap Creation (for digital sculpting packages)

MaCrea
http://drpetter.proboards.com/index.cgi?board=sculptris&action=print&thread=889

Perspective Grid Layout

Carapace (Windows only)
http://epicgames.com/community/2012/11/free-art-tool-released-thanks-to-epic-friday/

Math Graphics, Algebra, Tables, Statistics, and Calculus

GeoGebra
http://www.geogebra.org/cms/

3D Box Image creation from stills

3D Box Shot Maker
http://www.bosseye.com/boxshot/index.htm

Project & Asset Management

Southpaw Tactic
http://www.southpawtech.com/tactic/

Attract (Blender Institute)
https://cloud.blender.org/attract/

OrangeScrum
https://www.orangescrum.com/

Peragro
http://damn.csproject.org/

Prism-Pipeline
https://prism-pipeline.com/

GanttProject
http://www.ganttproject.biz/

Endeavour Management (possibly Windows only)
http://endeavour-mgmt.sourceforge.net/index.html

Tindio
http://e-pool-productions.github.io/tindio/

FTP transfer

Filezilla
https://filezilla-project.org/

Batch File Renaming

Bulk Rename Utility (Windows only)
http://www.bulkrenameutility.co.uk/Main_Intro.php

CKRename
http://www.softpedia.com/get/System/File-Management/CKRename.shtml

1-4a Rename
http://www.1-4a.com/rename/

Backup Software

FreeFileSync
http://freefilesync.sourceforge.net/

Cobian Backup
http://www.educ.umu.se/~cobian/cobianbackup.htm

NAS software

FreeNAS
http://www.freenas.org/

Windows Product Key Recovery

Keyfinder
http://www.magicaljellybean.com/keyfinder/

Programming Language for Digital Artists

Processing
http://processing.org/

Tracking Open Source code

TLD - Tracking Learning Detection
http://personal.ee.surrey.ac.uk/Personal/Z.Kalal/tld.html

Monitor Color Calibration

ColorHug (not free, but open source)
http://www.hughski.com/

Game Engine

ZGameEditor (Windows and Linux maybe, not sure)
http://zgameeditor.org/

Sylphis 3D (game engine)
http://devnet.sylphis3d.com/

Physically Based rendering free book
http://www.pbr-book.org/

Language Learning

Duolingo
https://www.duolingo.com/

Free 3D Models/Assets

Polycount BaseMesh collection
http://wiki.polycount.com/BaseMesh

https://www.yobi3d.com/

Free Textures
https://texturehaven.com/

https://www.sharetextures.com/

HDRI images

https://hdrihaven.com/

http://www.hdri-hub.com/hdrishop

http://www.openfootage.net/

http://www.moofe.com/

http://hdrmaps.com/freebies

Free Footage

http://www.hollywoodcamerawork.us/greenscreenplates.html

http://www.hollywoodcamerawork.us/trackingplates.html

Free music

http://musopen.org/

http://www.freesound.org/

http://audiojungle.net/ (only one free track a month)

Free sound effects

http://www.julianraymusic.com/sounds/soundblend/soundblend_DV.asp

http://www.freesound.org/

http://www.freesfx.co.uk/

http://www.philmichalski.com/ (some free libraries, others are under $3)

Space Flight Simulator

Orbiter 2010 (Not creative software, but neat! Windows only)
http://orbit.medphys.ucl.ac.uk/index.html

Follow the links to download the Software, search it on Google and Youtube for more details. Youtube is filled with video tutorials for most of these.

if you find a link that is incorrect or outdated, let me know, I’ll fix it.