Below is a non-exhaustive list of free and open source marketing tools categorized by functional area (repeated if something fits in multiple areas).

Special thanks to the editorial team and contributors at opensource.com, I found many of these resources in articles they have published over the years.

Update: This has grown a lot since I started it in August 2016. I recommend using the Find (Control + F) function in your browser if you are looking for something specific.

Analytics and Data

  • Data Visualization
    • Dashbuilder: A full featured web application to easily create dashboards from heterogeneous sources.
    • Bokeh: A Python interactive visualization library that targets modern web browsers for presentation.
    • freeboard: Internet of Things (IoT) device dashboard software.
    • Grafana: Tool for querying and visualizing time series and metrics.
    • Mozaïk: Scalable, extendable, responsive Node.js-based dashboard software.
    • Seaborn: Python visualization library for statistical data, based on matplotlib.
    • Stashboard: Status dashboard for APIs and software services.
  • Elastic Stack: Suite of analytics and search software.
    • Beats: Platform for single-purpose data shippers
    • Logstash: Server-side data processing pipeline that ingests data from a multitude of sources simultaneously.
    • Elasticsearch: A distributed, RESTful search and analytics engine
    • Kibana: Visualization tool for the Elastic Stack.
  • LimeSurvey: Web-based survey tool.
  • MySQL: Relational database management system.
  • Pentaho: Software suite of business intelligence products
  • Phant: Internet of Things (IoT) data logging service.
  • Piwik: Robust website analytics platform.
  • Pollen: Poll platform with various methods of voting.
  • PostgreSQL: Object-relational database management system.
  • Python: Interpreted language emphasizing readability and clarity.
  • R Software Environment: Statistical computing and graphics.
    • BBC R Cookbook: Guide to creating publication-ready graphics in the BBC’s in-house style, using R.
    • bbplot: R package that helps create and export ggplot2 charts in the style used by the BBC News data team.
    • ggplot2: A system for declaratively creating graphics in R, based on The Grammar of Graphics (book).

Animation and Digital Drawing

  • Blender: Complete 3D creation software suite.
    • Sprytile: Blender add-on for stylized, textured low poly models.
  • Elmyra: Blender-based industrial design visualization system
  • MyPaint: Raster graphics editor for digital painters.
  • Pencil2D: Animation software for bitmap and vector graphics.
  • Piskel: Editor for animated sprites and pixel art.
  • Synfig Studio: Vector-based 2D animation software.
  • Tupi: 2D animation software.

Audio Editing and Music

  • Ardour: Hard disk recorder and digital audio workstation software.
  • Audacity: Audio software for multi-track recording and editing.
  • Carla: Fully-featured audio plugin host, with support for many audio drivers and plugin formats.
  • CherryMusic: Music streaming server written in Python.
  • Clementine: A fast, easy to use, cross-platform music player.
  • cmus: A small, fast and powerful console music player for Unix-like operating systems.
  • Hydrogen: Advanced drum machine for pattern-based drum programming.
  • Libre.fm: A community where artists can share their music for everyone to enjoy.
  • LMMS: Music production software for melodies and beats, synthesizing and mixing sounds, and arranging samples with MIDI keyboard support.
  • Mixxx: DJ software platform with personal to professional capabilities.
  • Music Player Daemon (MPD): A flexible, powerful, server-side application for playing music.
  • Picard: A cross-platform application for tagging and organizing your music library
  • Qtractor: Audio/MIDI multi-track sequencer.
    • Calf Studio Gear: Audio plug-in pack for LV2 and JACK environments
    • Patchage: Modular patch bay for audio and MIDI systems based on JACK and ALSA.
    • QjackCTL: Application to control the JACK sound server daemon.
    • ZynAddSubFX: Fully featured open source software synthesizer.
  • Rhythmbox: An audio player that plays and helps organize digital audio.
  • Musicians creating freely licensed music:
  • * CC Search: Set of search services maintained by Creative Commons. Includes non-Free Content *
  • * Free Music Archive: Catalog of audio files. Includes non-Free Content *
  • * MusicBrainz: An encyclopedia of music information. Includes non-Free Content *

Audio/Video Equipment, Photography, Videography

Collaboration and Code-Sharing

  • Apache Subversion (SVN): Version control system software.
  • Collabora Cloudsuite: LibreOffice-based office suite that works across platforms and devices.
  • Etherpad: Customizable online editor providing real-time collaborative editing.
  • Git: Distributed version control system.
  • GitLab: Integrated product that unifies issues, code review, CI and CD into a single UI.
  • Mercurial: Distributed source control management tool.
  • Phabricator: Suite of web-based software development collaboration tools.

Communities

Education

Email

  • Evolution: Personal information management software (email, calendar, contacts).
  • Geary: Straightforward email client software.
  • phpList: Mailing list and email marketing software.
  • roundcube: Browser-based multilingual IMAP client with an application-like user interface.
  • Sylpheed: Simple, lightweight email client software.
  • Thunderbird: Easy desktop email application software.

Enterprise Resource Planning (ERP)

  • CiviCRM: ERP for not-for-profit organizations.
  • ERPNext: Simple, cloud-based ERP platform.
  • metasfresh: Feature-rich ERP platform.
  • Odoo: Suite of enterprise management applications.
  • OpenPetra.org: Free administration software for non-profits.

EBooks

  • Lucidor.org: Lightweight and cross-platform ebook platform (supports OPDS and EPUB).
    • Lucidor – ebook reader application.
    • Lucifox – ebook reader extension for Mozilla Firefox.
    • Luciwik – ebook system for MediaWiki.
    • Lucimoo – ebook system for Moodle.

File Conversion and Manipulation

  • ffmpeg:  A complete, cross-platform solution to record, convert and stream audio and video.
  • LibreOffice: Command line functionality to convert one or more files.
  • LosslessCut: Simple, cross platform video editor for lossless trimming and cutting of videos.
  • Pandoc: A universal document converter compatible with many file formats.
  • PDFtk: Toolkit with a variety of functions for manipulating PDF documents.
  • QPDF: Toolkit with a variety of functions for manipulating PDF documents.
  • unoconv: Universal converter for any document format supported by LibreOffice/OpenOffice.
  • Xpdf: PDF viewer that includes PDF-to-text functionality.

File Sync and Sharing

  • Nextcloud: A next generation platform for file sharing, synchronization, and more.
    • AppStore: Password management, video chat, document collaboration, etc.
    • Box: Home hardware device for hosting Nextcloud.

Forums and Community Management

  • Discourse: Full-featured Internet discussion platform.
  • phpBB: Flat-forum bulletin board software.

Funding and Financing

GNU/Linux Distributions (Operating Systems)

Graphic Design

  • gpick: Advanced color picker and palette editing tool.
  • Inkscape: Vector graphics editing software.
  • Krita: Sketching and painting software.
  • Scribus: Desktop publishing software.

IRC/Freenode

  • Channels:
    • #opensourcedesign
    • #opensource.com
  • Freenode: An IRC network used to discuss peer-directed projects.
  • IRC: Application layer protocol for text-based communication, with chat enabled by a client/server networking model.

Markdown

  • Markdown: Official project documentation.
  • Abricotine: Distraction-free interface with GitHub Flavored Markdown (GFM) support.
  • Elegant Markdown Editor: Focused markdown editor.
  • embedmd: Embed files or fractions of files into markdown files.
  • ghostwriter: Distraction-free markdown editor.
  • Laverna: Markdown note-taking app focused on privacy.
  • LightMd Markdown Editor: Lightweight markdown editor.
  • MarkMyWords: Minimal markdown editor.
  • odpdown: Generate ODP files from markdown.
  • PileMd: Markdown editor with notes and local syncing.
  • Remarkable: Fully featured, robust markdown editor with GitHub Flavored Markdown (GFM) support.
  • ReText: Simple but powerful markdown editor.
  • UberWriter: Simple, feature-rich markdown editor.

Mobile, Phone, and Tablet

  • Asterisk: Framework for building communications applications.
  • AntennaPod: Easy-to-use, flexible podcast player and manager for Android.
  • F-Droid: Repository of applications for the Android platform.
  • LineageOS: Operating system for smartphones and tablet computers.
  • OmniRom: Operating system for smartphones and tablet computers.
  • Ring: Distributed multi-media communication software.
  • SkyTube: Privacy-friendly, read-only access to YouTube videos for Android.

Office, Productivity, and Word Processing

Organizational Behavior

  • The Open Organization (Book) by Jim Whitehurst (CEO, Red Hat)
    • Definition: The five characteristics that define an open organization.
    • Field Guide: A community-produced companion book with insights from practitioners.
    • Leader’s Manual: A community-produced companion book with emphasis on leadership.
    • Maturity Model: A framework for helping your organization to become more transparent, inclusive, adaptable, collaborative, and communal.
    • Workbook: A handbook style resource for culture change initiatives aimed at cultivating open environments.

Organizations

Photo and Image Editing, Viewing and Processing

  • Enblend/Enfuse: Seamless image and exposure blending. [Check out MacroFusion GUI interface for Enfuse]
  • Fotoxx: Application for image editing and collection management.
  • GNU Image Manipulation Program: Image and photo editing software.
  • G’MIC: Full-featured framework for image processing with multiple user interfaces.
  • Geeqie: Lightweight image viewer software.
  • Ghiro: Automated, web-based digital image forensics tool. [Try it online here at imageforensic.org]
  • GraphicsMagick: Collection of tools and libraries supporting reading, writing, and manipulating image files in over 88 formats.
  • Hugin: Cross-platform panoramic imaging tool chain.
  • HDRMerge: Application that fuses two or more raw images into a single raw with an extended dynamic range with exposure merging and tone mapping.
  • ImageJ: Image processing and analysis in Java.
  • ImageMagick: Software for displaying, converting, and editing raster and vector image files.
  • LuminanceHDR: Graphical user interface that provides a complete workflow for HDR imaging.
  • Raw Processing
    • darktable: Photography workflow application and raw developer.
    • digiKam: A comprehensive set of tools for importing, managing, editing, and sharing photos and raw files.
    • filmulator: Film emulator for raw files from cameras that stimulates development of film mimicking light from the camera sensor.
    • LightZone: Professional-level digital darkroom and photo editor with RAW processing and editing.
    • Open Cine: Raw processing tool for moving images.
    • photivo: Photo processor for RAW and bitmap files in a non-destructive 16 bit processing pipeline.
    • Photoflow: A fully non-destructive photo retouching program providing a complete RAW image editing workflow.
    • RawTherapee: Powerful, cross-platform raw photo processing program.
    • UFRaw: Utility to read and manipulate raw images from digital cameras
  • Siril: Semi-automated processing tool for astronomical images.
  • VIPS: Fast, low memory usage image processing system.
  • Web Galleries:
    • coppermine gallery: Multi-purpose, fully-featured, and integrated web picture gallery script.
    • fgallery: Minimalist static photo gallery generator.
    • Pannellum: Lightweight, plug-in free panorama viewer for the web.
    • ResourceSpace: Simple and fast digital asset management software.
    • Gallery: Web-based photo management for your own website. Inactive/No longer maintained.

Project Management and Scheduling

  • Booked Scheduler: Simple reserve-anything scheduler for labs, rooms, events, and more.
  • Dudle: Event scheduler and meeting planning software.
  • Habitica: Gamified productivity software.
  • Kanboard: Simple, Kanban-style project management software.
  • OpenProject: Project management software.
  • Restyaboard: Fully-featured, Kanban-style project management software.
  • Taiga: Project management platform for agile developers and designers and project managers.
  • TaskBoard: Kanban-style project management software.
  • Wekan: Kanban-style project management software.

Screen Capture and Shots

Social Media

  • Circular: An open source application to queue social media posts.
  • GNU Social: Federated social communication software for public and private communication.
  • Mastodon: An alternative, implementation of the federated social communication software GNU Social.
  • Rainbowstream: Beautiful command line Twitter client.
  • Tusky: Client for microblogging network Mastodon.
  • Twidere: Fully featured microblogging service application (e.g. Mastodon, Twitter).
  • Twidge: Simple command line Twitter client.

Stock Content

Text Editors

  • Gedit: Text editor for GNU/Linux, Mac OS X, and Windows.
  • Notepad++: Text editor for Windows.
  • TextMate: Text editor for Mac OS X.

Translation

  • Computer-Assisted Translation (CAT) Tools – Accelerate and aid the process of translation and translation review.
    • Anaphraseus: LibreOffice Extension for creating, managing and using bilingual Translation Memories.
    • OmegaT: Translation memory application for professional translators.
    • * OmegaT+: Tools for use by translators, localization engineers, and other language professionals. Inactive/No longer maintained. *
    • OpenTM2: Program for managing and handling global translation projects.
    • Subtitles Translator: Program for translating subtitles in MicroDVD format from one language to another.
  • Localization Automation Tools – Tools that save time by facilitating the process of localizing data.
    • Okapi Framework: Set of components and applications that offer extensive support for localizing and translating documentation and software.
    • Mojito: Automation platform that enables continuous localization
  • Machine Translation (MT) Engines – Automate translation from one language to another.
    • Apertium: Toolbox to build shallow-transfer machine translation systems, especially for related language pairs.
    • Moses: System that allows you to automatically train translation models for any language pair.
  • OpenSpeaks: Community for documenting, learning, and sharing languages.
    • Kathabhidhana: Toolkit to record a large number of words in any language.
  • Open Translation Tools Manual (PDF) (EPUB) (HTML)
  • Terminology Management Systems – Tools with a graphical user interface (GUI) for terminology resources (“termbases”) that aid translation.
    • BaseTerm: Terminology management system built with the primary goal of natively supporting TBX-Basic.
    • terminator: Online terminology management and discussion tool.
  • Translation Management Systems – Web-based platforms to manage localization projects.
    • GlobalSight: System that automates, streamlines, and manages the localization process.
    • Jabylon: Open-source translation server.
    • Pontoon: In-place web content localization tool.
    • Pootle: Online translation and localization tool.
    • translate5: Modern, cloud-based translation management system.
    • Weblate: Simple, clean web-based translation tool with tight version control integration.
    • Zanata: Web-based translation platform to manage localization projects.

Typeface, Typography and Fonts

Video Editing and Animation

  • Blender: Complete 3D creation software suite.
  • Kdenlive: Non-linear video editing software.
  • OpenShot: Simple video editing software.
  • Piskel: Editor for animated sprites and pixel art.

Web Browser and Search

Web Development

  • Aptana Studio: Integrated development environment for web applications.
  • Bootstrap: HTML/CSS/JS web development framework.
  • BlueGriffon: HTML editor.
  • Django: High-level Python Web framework.
  • Drupal: Content-management framework written in PHP.
  • Firefox Add-on – Firebug: A web development add-on for Firefox.
  • Firefox  Add-on – Web Developer: A web development add-on for Firefox.
  • Flask: Microframework for Python based on Werkzeug and Jinja 2.
  • HTML5: Latest version of HTML and XHTML
  • Kompozer: HTML editor.
  • Let’s Encrypt: Free SSL/TLS certificates.
  • Mapillary: Crowd-sourced street-level imagery and map data platform.
  • Mautic: Marketing automation platform for landing pages, email, social media, and more.
  • MJML: Responsive email framework.
  • Observatory: Set of tools to analyze website security.
  • Open Street Map: Comprehensive global mapping project.
  • PatternFly: UI framework for enterprise web applications.
  • Phaser: Desktop and mobile HTML5 game framework.
  • Piwik: Robust website analytics platform.
  • Precursor: Fast, collaborate web development prototyping tool.
  • Reveal.js: HTML presentation framework.
  • Ruby on Rails: Web application framework.
  • SeaMonkey: Internet suite (all-in-one browser, email, news, chat, and editor).
  • Twemoji: Cross-platform library that provides standard Unicode emoji support.
  • WordPress: Content management system based on PHP and MySQL.

Writing

  • documentation.js: Beautiful documentation generator.
  • Fountain: Plain text markup language for screenwriting and screenplays.
  • LaTeX: Document preparation system for typesetting.
  • Plume Creator: Software for writers and novelists.
  • Read the Docs: Documentation framework and hosting service.
  • ‘afterwriting: A client-side node.js web application for screenwriting with local/offline functionality.

3D Modeling (Desktop)

  • Blender: Complete 3D creation software suite.
  • FreeCAD: Parametric 3D modeling software.
  • OpenSCAD: Script-based desktop for creating 3D models.

3D Modeling (Web/Browser)

3D Models

  • vectiler: A wavefront OBJ vector tile builder and exporter based on mapzen vector tiles.
  • * Thingiverse: 3D model repository. Includes non-Free Content *
  • * Yeggi: 3D model search engine. Includes non-Free Content *
  • * YouMagine: 3D model repository. Includes non-Free Content *

Miscellaneous

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