Oh sure, you can run Linux apps on the Linux desktop. Obviously. But Linux developers aren't content to stay confined. As a sign of Linux's ever expanding influence, the Windows desktop also has an sprawling menu of open source apps. The following list is a mix of applications for home, business and education users from a broad range of categories.
With the end of life for Windows XP approaching, many Windows users may be looking particularly for software that runs on Windows 7 or Windows 8. To meet their needs, we've noted which versions of Windows each application supports, where possible. (Note that not all of the open source applications on the list specify with versions of Windows are supported.)
Some of the applications on the list run on Windows only, but others also run on Linux or OS X.
As always, if you think we should have included other open source applications in our list, please feel free to note them in the comments section below.
If you're a Windows user with no previous open source experience, OpenDisc is a good place to start. It's a collection of many of the most popular open source applications for Windows, including Blender, the Gimp, Scribus, Firefox, Thunderbird, Audacity, Celestia, VLC, LibreOffice and many more. Operating System: Windows
This open source Windows app collection is portable, meaning you can install it on a thumb drive or a cloud service so that you can use your favorite apps from any system. In addition to the collection, the site also features portable versions more than 300 other open source and freeware apps. Operating System: Windows (8, 7, Vista and XP)
Similar to PortableApps.com, winPenPack is a collection of open source applications that can be installed and run from a thumb drive. It comes in two pre-configured versions—Essential and Full—as well as a Personal version that users can customize themselves. Operating System: Windows.
Used by more than 600,000 people, ClamWin is based on the popular Clam AV antivirus engine used by many Linux users. It integrates with Windows Explorer and Microsoft Outlook. Users should note that it requires manual scanning of files in order to detect malware; in other words, you have to click on a file in order to scan it. Operating System: Windows (8, 7, Vista, XP, Me, 2000, 98, Server 2012, Server 2008, Server 2003)
Popular with science teachers and space buffs of all ages, Celestia allows users to see the night skies as they would appear from any point in the known universe, at any point in time. The project's main website has been down recently. The link above will take you to the Sourceforge page, and you can also find information and add-ons at the Celestia Motherlode website. Operating System: Windows, Linux, OS X
The brains behind many planetarium displays, Stellarium shows the night skies as they appear to the naked eye from points on earth. The default installation includes more than 600,000 stars, but you can also add other catalogs that include more than 210 million stars. Operating System: Windows (32- and 64-bit), Linux, OS X.
An alternative to iTunes, Amarok aims to make it easy to discover and listen to your favorite music. It boasts an attractive, easy-to-use interface and integration with a wide variety of Web-based music services. Operating System: Windows (8, 7, Vista, XP), Linux, OS X, iOS
For the Linux community, Audacity has long been the go-to tool for recording and editing audio. Although not intended for use by professional recording studios, it has all the features home users and hobbyists are likely to need or want. Operating System: Windows (7, 8, Vista, XP, 2000), Linux, OS X
Based on the same code as Amarok, Clementine developers have focused on creating a fast, easy-to-use interface for this audio player. The latest version also includes the ability to control it remotely with an Android phone. Operating System: Windows (8, 7, Vista, XP), Linux, OS X, Android
If you're a musician, there's no need to spend tons of money on an application to print sheet music. Easy-to-use Musescore prints beautifully, and it's completely free. Operating System: Windows (8, 7, Vista, XP), Linux, OS X
The Advanced Maryland Automatic Network Disk Archiver, a.k.a. AMANDA, claims to be the most popular open source backup software in the world. Aimed at organizations, it backs up networks, not standalone machines. Zmanda, which sponsors the project, offers a cloud-based solution based on the same code. Operating System: Windows (7, Vista, XP Pro, Server 2008, Server 2003), Linux, OS X
12. Areca Backup
Made for home users, Areca backs up standalone systems. It's highly versatile and offers compression, encryption, and support for most storage media. Operating System: Windows, Linux
Downloaded more than 750,000 times, Redo aims to make backup and recovery very easy for home users. It claims to be able to do bare metal restores in as little as ten minutes. Operating System: Windows, Linux
Immensely popular, WordPress runs more than 60 million websites and blogs. The code at this site will allow you to set up your own server, or you can use the free hosted service at WordPress.com Operating System: Windows (8, 7, Vista, XP, Server 2012, Server 2008 R2, Server 2008, Server 2003), Linux, OS X, iOS, Android, BlackBerry, Windows Phone, others
This is the open source project that provides the basis for the Chrome browser. It aims to be safer, faster and more stable than other browsers. Operating System: Windows (8, 7), Linux, OS X, Chrome OS, iOS, Android
One of the most widely used open source applications, Mozilla's Firefox browser offers advanced performance, security and customization capabilities. Key features include the awesome bar, a pinnable tabbed interface, synchronization, integrated search and more. Operating System: Windows (8, 7, Vista, XP, Server 2003), Linux, OS X, Android
17. Tor Browser
If you're worried that people might be spying on your Internet usage—or if you are a spy and don't want people to know what you're up to—Tor offers anonymous Web browsing. It makes communications untraceable by bouncing them around a network of secure servers and relays. Operating System: Windows (8, 7, Vista, XP), Linux, OS X
Under development since 1979, BRL-CAD is a package of more than 400 tools, utilities and applications for creating 2D and 3D solid geometry models. Its best-known user is the U.S. military. Operating System: Windows, Linux, OS X, others
Track projects, milestones and tasks for group projects in the cloud with Collabtive. It's very similar to Basecamp and will even import Basecamp data. Operating System: OS Independent
20. Feng Office
Built to offer project management for professional services organizations, Feng Office boasts more than 1 million users in more than 150 different countries. In addition to the free download, it also comes in cloud-based or paid on-site versions. Operating System: Windows, Linux, OS X
PeaZip supports more than 150 different archive file formats, including some that offer very tight compression. It can also convert, split, encrypt or securely delete compressed files. Operating System: Windows (8, 7, Vista, NT, XP, 2000, 9x), Linux, OS X.
Used by companies like Bank of America, BP, Hilton, Samsung and Kaiser Permamente, DNN is one of the most popular open source Web platforms for business. Paid and free versions are available. Operating System: Windows (8, 7, Vista, Server 2008, Server 2012)
Drupal boasts a community of more than 1 million people from 230 different countries. Extremely popular, its users include AOL, Harvard, MIT, San Jose State University, MTV, Sony Music and many others. Operating System: OS Independent
Downloaded more than 35 million times, Joomla runs millions of websites, including those of Ebay, Barnes & Noble, GE and Ikea. It's won numerous awards and has a very active community of users. Operating System: OS Independent
Plone claims to be "among the top 2% of all open source projects worldwide," as far as the size of its development team and user base. Its goal is to create websites that are fast, powerful and beautiful. Operating System: Windows, Linux, OS X
Customer Relationship Management (CRM)
26. Sugar Community Edition
Millions of people around the world use the Sugar CRM platform. Organizations can host the free version of the software themselves or use one of the cloud-based paid editions. Operating System: OS Independent
The self-proclaimed "true universal open source database," Firebird has been under development since 1981. It boasts "excellent concurrency, high performance, and powerful language support for stored procedures and triggers." Operating System: Windows (7, Vista, XP, NT, ME, 9x, Server 2000, Server 2003, Server 2008), Linux, Unix, OS X, Solaris
The "world's most popular open source database," MySQL provides the foundation for many Web applications, including Twitter, Tumblr, LinkedIn, PayPal, craigslist and others. It comes in many different free and paid editions. Operating System: Windows, Linux, Unix, OS X
PostgreSQL calls itself "the world's most advanced open source database." Key features include support for multiple platforms, full ACID compliance, support for multiple programming languages, Multi-Version Concurrency Control (MVCC), point in time recovery, tablespaces, asynchronous replication, nested transactions (savepoints), online/hot backups and more. Operating System: Windows, Linux, OS X
If your system is running slow or you have concerns about privacy, BleachBit is for you. It can securely delete files and clean out your Internet history, cache, temporary files, logs, cookies and other junk. Operating System: Windows (7, Vista, XP), Linux
DBAN securely deletes all of the information on a hard drive. It's a great tool to have on hand when you're recycling old systems. Operating System: OS Independent
32. Electric Sheep
One of the most interesting screensavers ever created, Electric Sheep connects thousands of "sleeping" systems to create collaborative pieces of art. The name and the concept come from Philip K. Dick's novel Do Androids Dream of Electric Sheep? Operating System: Windows (XP or newer), Linux, OS X, Android, iOS
Leave yourself digital sticky notes on your desktop. Key PNotes features include portability, rich text formatting options, skins, overdue tracking, LAN exchange, social network integration, password protection, encryption, tags and much more. Operating System: Windows (8, 7, Vista)
One of the great features of desktop Linux is the ability to create virtual desktops; VirtuaWin adds the same functionality to Windows. Excellent for multi-tasking, it allows you to group together sets of open windows and switch between them. Operating System: Windows (7, Vista, 2003, XP, 2000, NT, ME, 9x)
Suitable for professional use, Scribus is an advanced page layout program similar to Publisher, QuarkXpress or InDesign. It can create press-ready output or PDFs. Operating System: Windows (8, 7, Vista, 2000, Server 200x, Linux, OS X
If you already use the Firefox browser, Thunderbird makes a great companion app as it offers an email client with a similar interface. To make it more like Outlook, you can also add Lightning for calendar functionality. Operating System: Windows (7, Vista, XP, 2000, Server 2003), Linux, OS X
This very popular Windows encryption app boasts nearly 3 million registered users. It integrates with Windows Explorer—just right-click to encrypt files and double-click to open them. It also works with cloud storage services like DropBox and Google Drive. Operating System: Windows (8, 7, Vista, XP, 2003)
Encrypt your files or mail using GNU Privacy Guard (GPG) technology. It's easy to install and use, and professional support is available from third-party companies. Operating System: Windows (8, 7, Vista, XP)
Another very popular encryption option, TrueCrypt can encrypt an entire disk or a partition. It offers fast performance thanks to parallelization and pipelining features. Operating System: Windows (7, Vista, XP), Linux, OS X.
Enterprise Resource Planning (ERP)
This community-managed ERP solution includes HR, sales, purchasing, manufacturing, materials, finance, maintenance and project management features. It integrates with several other well-known open source enterprise applications to add ecommerce, business intelligence, document management and other capabilities. Operating System: Windows, Linux, OS X, others
41. Apache OFBiz
Managed by the Apache Foundation, this enterprise automation suite includes CRM, e-commerce, supply chain, manufacturing, maintenance management, and point of sale capabilities, as well as traditional ERP features. It attempts to be "as good or better than those available from major proprietary ERPs at a significantly lower total project cost." Operating System: OS Independent
This award-winning software boasts that it's the "most modern, adaptable and lowest cost ERP solution available." It's available in enterprise or community editions, as well as a cloud-ready version. Operating System: Windows, Linux, OS X
The "leading Web-based business applications for the cloud," Openbravo is a suite of Web-based software for managing businesses. In addition to the free community version, it comes in several paid versions, including some tailored for various vertical markets. Operating System: OS Independent
The self-proclaimed "worlds #1 open source ERP software" comes in multiple cloud-based or on-site versions, in addition to the free PostBooks edition. Paid add-ons, services and support are also offered. Operating System: Windows, Linux, Unix, OS X
45. 0 A.D.
This award-winning real-time strategy game is similar to Age of Empires. Players choose a civilization and build their cities while combating opponents. Operating System: Linux, Windows (8, 7, Vista, XP, 2000), OS X
46. Alien Arena
A fast-paced first-person shooter, Alien Arena offers "immersive arenas, freaky and violent weapons, and a vibrant community." That graphics are excellent, and there are plenty of online games to connect with. Operating System: Linux, Windows, OS X.
Another first-person shooter, AssaultCube Reloaded aims to incorporate some of the best features from various commercial games. Key features include ricochet shots, anti-cheat, many different wapons, realistic gameplay and more. Operating System: Windows (7, Vista, 2000, Server 2003), Linux
This incredibly sophisticated flight simulator rivals commercial applications. It includes realistic models of more than 20,000 real airports and many different aircraft. Plus, the active community of users is always expanding its capabilities with new planes and additional scenery. Operating System: Windows (8, 7, Vista, XP), Linux, OS X, others
49. Frets on Fire
Very similar to Guitar Hero, Frets on Fire challenges users to play along with their favorite songs using a guitar controller or the keyboard. You can create your own songs, import songs created by the community of users or import Guitar Hero songs. Operating System: Windows, Linux, OS X
Designed for young children, this project brings together more than a hundred different educational games. It includes activities related to math, keyboarding, piano composition, geography, science, chess, reading and much more. Operating System: Windows (7, Vista, XP, 2000), Linux.
In this real-time strategy game, players choose to play as Tech, Magic, Egypt, Indians, Norsemen, Persian or Romans. The game world is incredibly detailed and many multi-player game servers are available. Operating System: Windows, Linux
This excellent Texas Hold 'Em app offers both single- and multi-player games. The interface is very attractive and you can easily change the style or create one of your own. Operating System: Windows, Linux, OS X, Android
53. Rigs of Rods
This popular vehicle simulator has a very active community constantly creating new vehicles and scenery. It uses a unique soft-body physics engine to create realistic models of land, sea or airborne vehicles. Operating System: Windows, Linux, OS X
Short for "The Open Race Car Simulator," (TORCS) is a very realistic racing game. Play using a keyboard, mouse, joystick or steering wheel controller. Operating System: Windows (32- and 64-bit), Linux, OS X
Head to the year 2084 in this squad-based tactical strategy game. Save the earth from alien invaders while playing in single- or multi-player mode. Operating System: Windows (XP or newer), Linux, OS X
This cartoonish game calls itself "the most fast-paced sport on the web!" Players fight against "rocketlauncher-wielding pigs and lasergun-carrying cyberpunks" in a game that isn't as gory as most first-person shooters. Operating System: Windows, Linux, OS X
57. Warzone 2100
Warzone transports users to the year 2100, where they must rebuild civilization following a nuclear apocalypse. Play in campaign, multi-player or single-player mode. Operating System: Windows (8, 7, Vista, XP), Linux, OS X
Lots of weapons and addictive gameplay make Xonotic a hit with gamers who enjoy first-person shooters. If you've ever played the game Nexuiz, this game will feel familiar. Operating System: Windows, Linux, OS X
Blender is a professional-caliber 3D animation suite that offers modeling, rigging, animation, simulation, rendering, compositing and motion tracking, video editing and game creation capabilities. The team behind the software is also involved in the creation of open movies, and a new project is currently in the works. Operating System: Windows (8, 7, Vista, XP), Linux, OS X
Dia is "roughly inspired by" Microsoft Visio and offers similar tools for creating charts and graphics. It's a good option for making simple org charts and diagrams, but it's not quite as advanced as Visio. Operating System: Windows (8, 7, Windows Vista and Windows XP), Linux
Short for "GNU Image Manipulation Program," Gimp is a very sophisticated, professional-quality graphics tool for photo retouching, image composition and image authoring. It supports most image file formats and offers a customizable interface, photo enhancement tools, a channel mixer, and much more. Operating System: Windows (8, 7, Vista, XP, Server 2003, Server 2008, Server 2012), Linux
Also suitable for professional use, Inkscape provides tools for the creation and editing of vector graphics. It's a great tool for creating logos, illustrations and scalable artwork. Operating System: Windows (7, Vista, XP), Linux, OS X
Human Resource Management (HRM)
63. Orange HRM
With more than a million users, OrangeHRM claims to be "the world’s most popular Open Source Human Resource Management Software (HRMS)." In addition to the free community version it also comes in paid professional and enterprise versions, with add-on services also available. Operating System: Windows (7, XP, Server 2003, Server 2008), Linux, OS X
If you're drafting a speech, preparing for a debate or writing a position paper, Argumentative can help you map out your argument visually. You can also export those graphics to Word, PowerPoint, text or Web formats. Operating System: Windows.
Descended from a project that began in the 1960s, Maxima is an algebra system that handles differentiation, integration, Taylor series, Laplace transforms, ordinary differential equations, systems of linear equations, polynomials, and sets, lists, vectors, matrices, and tensors. It can also plot graphs in two or three dimensions. Note that like most math software, it requires users to have some knowledge of programming. Operating System: Windows, Linux, OS X.
A suite that includes more than 100 different open source projects, Sage can perform many types of mathematical calculations, from elementary to advanced, pure and applied. It's very powerful but not particularly user-friendly; it's best for users familiar with the Python programming language.Operating System: Windows, Linux, OS X
One of the more polished open source math applications, Scilab supports thousands of different mathematical functions. Paid support, training and services can be purchased through Scilab Enterprises. Operating System: Windows (8, 7, Vista, XP), Linux, OS X
A great tool for brainstorming or organizing your thoughts, FreeMind makes it easy to create graphical representations of the connections between words, much like you would on a white board. Very popular, it's downloaded an average of 4,000 times every day. Operating System: Windows (7, Vista, XP, 2000, NT, 9x, Server 2003), Linux, OS X
Forked from FreeMind, FreePlane offers many of the same capabilities as its predecessor. To see it in action, check out the mind map explaining its functions. Operating System: Windows, Linux, OS X
Multimedia and Video Tools
Ideal for educators and helpdesk personnel, CamStudio makes it easy to record what is happening on a computer screen. It can also record sound. Operating System: Windows (7, Vista, XP)
This tool makes it easy to burn CDs and DVDs. It can crate data, audio and mixed-use discs, as well as erasing rewritable discs. Operating System: Windows
Miro calls itself "The beautiful, open-source music and video player that lets you break free." Key features include easier import from iTunes, Android syncing, a music and app store, support for most video file formats, video conversion capabilities, ultra-fast torrent downloads and more. Operating System: Windows, Linux, OS X, Android, iOS
73. VLC Media Player
VLC's claim to fame is that it plays just about everything. It's simple, fast, easy-to-use and doesn't require any extra codec packs to operate. Operating System: Windows (XP or later), Linux, OS X, others.
If you miss older versions of Word that didn't have the "ribbon," AbiWord might be a good choice for you. It can open and save documents to and from other word processing program formats, including Word and OpenOffice.org. Operating System: Windows (95 or later), Linux, OS X, others
Gnumeric aims to be "free, fast, accurate." It supports a huge number of functions (including many that Excel doesn't have), and it can import and export from other spreadsheet applications. Operating System: Windows, Linux
Very similar to OpenOffice (below), LibreOffice includes Office-compatible word processor (Writer), spreadsheet (Calc), database (Base) and presentation (Impress) software, plus, graphics (Draw) and math/science notation (Math). The latest version includes integration with popular content management systems, Firefox themes, and support for documents created in Visio or Publisher. Operating System: Windows (8, 7, Vista, XP), Linux, OS X
This Apache Foundation software includes the same set of applications as LibreOffice (above) with a very slightly different feature set. Under development for more than twenty years, it’s a very mature project that is easy to use and compatible with Microsoft file formats. Operating System: Windows (8, 7, Vista, 2003, XP), Linux, OS X
If you have a beginning typist or a budding writer at your house, WriteType is a great first word processing program. It includes student-friendly features like word completion, auto-correction, document read-back, grammar checking and more. Operating System: Windows, Linux
It's not even two years old yet, but Chamilo has already attracted more than a million users. It integrates easily with many other applications and includes adaptive assessment, social and mobile learning, skills management and other capabilities. Operating System: Windows, Linux, Unix, OS X
Used in more than 100 countries, Claroline has a large international community. It boasts an intuitive interface, flexibility, modular architecture, scalability and stability. Operating System: Windows, Linux, OS X
The ILIAS website says it is the first open source learning management system in the world to achieve SCORM 2004 (3rd Edition) compliance. It's another international favorite with an active user community and extensive documentation available. Operating System: Windows, Linux
With 65 million users, Moodle is one of the most popular open source applications of any kind. It's easy to use, flexible, customizable, scalable and secure. Operating System: Windows, Linux, OS X
The Sakai learning management solution offers the modules typically needed for teaching an online class, such as assignments, calendar, forum, chat, gradebook, tests, etc., and ePortfolio capabilities that allows students to showcase their work. The same group is also working on a related project for collaborating on research. Operating System: OS Independent.
If you have too many passwords to remember, KeePass offers a secure alternative to writing them down or using the same password multiple times. It stores unique passwords in an encrypted database that users can unlock with a single master password. You can install it on Windows Vista or later systems, or use it from a USB drive on older systems. Operating System: Windows
85. Password Safe
Designed by security expert Bruce Schneier, this award-winning app has been downloaded more than 4 million times. It offers very similar functionality as KeePass. Operating System: Windows (8, 7, Vista, XP)
With this helpful tool you can create a PDF file from almost any document. It can also do encryption, password protection and digital signatures. Operating System: Windows (2000 or later)
If you have a PDF file that you need to edit, PDFedit can do the trick. It has an easy-to-use GUI for Windows users, and it also operates from the command line. Operating System: Windows, Linux
Personal Financial Management
Now nearly twenty years old, this financial management software is easy to use and can import and export to and from popular applications like Quicken and Money. Noteworthy features include duplicate detection, scheduled transactions, tagging, reminders, category splits, budgeting, dynamic reports, auto-completion and more. Operating System: Windows, Linux
This double-entry accounting package strives to provide the same features as commercially available software, and it comes very close to that goal. It's very easy to use and has an attractive interface. Operating System: Windows, Linux, OS X
Web-based Achievo includes project management, scheduling and time tracking. Paid support is available through partner organizations. Operating System: Windows, Linux, OS X.
91. Project Libre
Awarding Project Libre specifically aims to be an open source replacement for Microsoft Project. The group of developers behind the application is also working on a project portfolio management (PPM) application. Operating System: Windows, Linux, OS X
This virtual private network (VPN) solution allows secure access to an organization's network for workers who are off-site or using their own hardware. In addition to the free community version, the company behind the project also offers a paid solution and a paid VPN service. Operating System: Windows, Linux, OS X, Android, iOS
Popular with schools around the world, OpenAdmin has been downloaded more than 26,000 times. It's Web-based and can be used for a single school or to manage multiple schools within a district. Operating System: OS Independent.
This web-based school management system "focuses on excellence and evolution in the field of education" with an emphasis on supporting the latest trends. It comes in both a free, open source version and a paid, supported edition. Operating System: Windows, Linux, OS X.
This popular student information system offers separate applications for K-12 schools, higher education and trade schools, hybrid and online schools, and district management. It's available in free, paid and cloud versions. Operating System: Windows (7, Vista, XP, Server 2008, Server 2003), Linux.
This screenwriting, storyboarding, scheduling and budgeting tool claims to be the "#1 choice for pre-production." The desktop app is available under an open source license, but the mobile apps and online syncing and collaboration tools require a paid account. Operating System: Windows (7, Vista, XP, Server 2003), Linux, OS X
Great for independent professionals and small teams that bill by the hour, eHour tracks clients, projects and time spent. It's Web-based and flexible, and it comes in multiple languages. Operating System: Windows, Linux, OS X
Another option for tracking worker time, TimeTrex had modules for scheduling, attendance, job costing and payroll. In addition to the free open source version, it comes in a variety of paid on-site and cloud editions. Operating System: Windows (2000 or newer), Linux, OS X
This app combines calendar functionality with a journal and can be used as a free alternative to Evernote. Use it to document your life diary-style or to keep track of notes about upcoming events. Operating System: Windows, Linux
If you're a website editing newbie, Kompozer is an excellent option. It offers a WYSIWYG editor and Web file management, as well as an HTML editor for those who are more advanced. Operating System: Windows, Linux, OS X
Based on a lot of the same code as Firefox, SeaMonkey combines a browser, email and newsgroup client, IRC chat client and an HTML editor in a single package. It's a very mature project and available in a couple of dozen different languages. Operating System: Windows (7, Vista, XP, 2000), Linux
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