Browse free open source C# Frameworks and projects below. Use the toggles on the left to filter open source C# Frameworks by OS, license, language, programming language, and project status.

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  • 1
    BepInEx

    BepInEx

    Unity / XNA game patcher and plugin framework

    Unity / XNA game patcher and plugin framework. BepInEx is a plugin / modding framework for Unity Mono, IL2CPP, and .NET framework games (XNA, FNA, MonoGame, etc.) Stable builds are released once a new iteration of BepInEx is considered feature-complete. They have the least bugs, but some newest features might not be available. Bleeding edge builds are available on BepisBuilds. Bleeding edge builds are always the latest builds of the source code. Thus they are the opposite to stable builds: they have the newest features and bugfixes available, but usually tend to be the most buggy. Therefore you should use bleeding edge builds only if you are asked to or if you want to preview the upcoming version of BepInEx. Some games require some additional changes in order to work around specific limitations of different Unity versions.
    Downloads: 355 This Week
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  • 2
    Selenium

    Selenium

    Browser automation framework and ecosystem

    Selenium automates browsers. That's it! What you do with that power is entirely up to you. Primarily it is for automating web applications for testing purposes, but is certainly not limited to just that. Boring web-based administration tasks can (and should) also be automated as well. If you want to create robust, browser-based regression automation suites and tests, scale and distribute scripts across many environments, then you want to use Selenium WebDriver, a collection of language specific bindings to drive a browser - the way it is meant to be driven. If you want to create quick bug reproduction scripts, create scripts to aid in automation-aided exploratory testing, then you want to use Selenium IDE; a Chrome and Firefox add-on that will do simple record-and-playback of interactions with the browser. If you want to scale by distributing and running tests on several machines and manage multiple environments from a central point.
    Downloads: 128 This Week
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  • 3
    PowerShell

    PowerShell

    Command-line shell and scripting language built on .NET

    Powershell is a cross-platform, task-based command-line shell and scripting language that helps rapidly automate tasks that manage operating systems (Linux, macOS and Windows) and processes. It works well with existing tools and is optimized for dealing with structured data, REST APIs and object models. PowerShell was developed by Microsoft as a task management and configuration management framework. Powershell is designed to let you manage computers from the command line and improve the command-line and scripting environment.
    Downloads: 106 This Week
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  • 4
    NBFC

    NBFC

    NoteBook FanControl

    NBFC is a cross-platform fan control service for notebooks. It comes with a powerful configuration system, which allows to adjust it to many different notebook models. Currently, there are no pre-built releases for Linux, but you can easily build NBFC yourself. In general the NBFC Wiki is the first place to go if you have any questions. If you want to build NBFC from source, the first thing you have to do is to download the source code. You can easily clone the NBFC repository via git. Make sure the Mono runtime + development tools are installed on your machine (Debian based distros: mono-complete, Arch based distros: mono). Config files are an integral part of NBFC, because they define how NBFC interacts with your notebook's embedded controller (EC). The EC, among other things, monitors your system's temperatures and controls the fan(s). It usually sits on the motherboard or is integrated into a Super I/O chip and is connected to the Southbridge via the Low Pin Count (LPC) bus.
    Downloads: 76 This Week
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    mpv.net

    mpv.net

    mpv.net is a modern media player for Windows that works just like mpv

    mpv.net is a modern desktop media player for Windows based on the popular mpv player. mpv.net is designed to be mpv compatible, almost all mpv features are available because they are all contained in libmpv, this means the official mpv manual applies to mpv.net. mpv focuses on the usage of the command line and the terminal, mpv.net retains the ability to be used from the command line and the terminal and adds a modern Windows GUI on top of it. Video output that is capable of many features loved by videophiles, such as video scaling with popular high-quality algorithms, color management, frame timing, interpolation, HDR, and more. Leverages the FFmpeg hwaccel APIs to support DXVA2 video decoding acceleration. mpv.net is based on libmpv which offers a straightforward C API that was designed from the ground up to make mpv usable as a library and facilitate easy integration into other applications. mpv is like VLC not based on DirectShow or Media Foundation.
    Downloads: 70 This Week
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  • 6

    Emgu CV

    Emgu CV is a cross platform .Net wrapper for OpenCV

    Emgu CV is a cross platform .Net wrapper to the OpenCV image processing library. Allowing OpenCV functions to be called from .NET compatible languages such as C#, VB, VC++, IronPython etc. The wrapper can be compiled in Mono and run on Windows, Linux, Mac OS X, iPhone, iPad and Android devices.
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    Downloads: 316 This Week
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  • 7
    CefSharp

    CefSharp

    .NET bindings for the Chromium embedded framework

    CefSharp is an easy way to embed a full-featured standards-compliant web browser into your C# or VB.NET app. CefSharp has browser controls for WinForms and WPF apps, and a headless (offscreen) version for automation projects too. CefSharp is based on Chromium Embedded Framework, the open source version of Google Chrome. CefSharp embraces modern web standards, and supports HTML5, JavaScript, CSS3 and HTML5 audio/video elements. 3D content is supported via WebGL which uses OpenGL/DirectX for hardware accelerated rendering. CefSharp includes embedded modules for PDF, web page printing and the WebKit Inspector (developer tools). CefSharp has no external dependencies, and the full build of CefSharp only adds ~80 MB to your app. See the CefSharp.MinimalExample project for ready-to-compile minimal example apps built with CefSharp. Within the projects source there are more complicated example projects.
    Downloads: 55 This Week
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  • 8
    Grassroots DICOM

    Grassroots DICOM

    Cross-platform DICOM implementation

    Grassroots DiCoM is a C++ library for DICOM medical files. It is accessible from Python, C#, Java and PHP. It supports RAW, JPEG, JPEG 2000, JPEG-LS, RLE and deflated transfer syntax. It comes with a super fast scanner implementation to quickly scan hundreds of DICOM files. It supports SCU network operations (C-ECHO, C-FIND, C-STORE, C-MOVE). PS 3.3 & 3.6 are distributed as XML files. It also provides PS 3.15 certificates and password based mecanism to anonymize and de-identify DICOM datasets.
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    Downloads: 163 This Week
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  • 9
    StabilityMatrix

    StabilityMatrix

    Multi-Platform Package Manager for Stable Diffusion

    StabilityMatrix is a project that helps organize, evaluate, and compare generative AI models and their behavior across prompts, datasets, or configuration settings. It provides a framework to run experiments systematically—capturing inputs, model configurations, outputs, and metrics—so researchers and practitioners can reason about differences in quality, robustness, and failure modes. The repository often bundles tooling for automated prompt sweeping, scoring heuristics (such as diversity, coherence, or task-specific metrics), and visualization helpers to make comparisons interpretable. This approach is useful for model selection, prompt engineering, and benchmarking new checkpoints against baseline models under reproducible conditions. By turning ad-hoc tests into tracked experiments, StabilityMatrix reduces bias, surfaces subtle regressions, and accelerates iteration when tuning generative systems.
    Downloads: 27 This Week
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  • 10
    NHibernate
    .NET port of the excellent Java Hibernate which provides Object/Relational mapping to persist objects in a relational database.
    Downloads: 110 This Week
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  • 11
    .NET Runtime

    .NET Runtime

    Cross-platform runtime for cloud, mobile, desktop, and IoT apps

    .NET is a free, cross-platform, open source developer platform for building many different types of applications. With .NET, you can use multiple languages, editors, and libraries to build for web, mobile, desktop, games, and IoT. You can write .NET apps in C#, F#, or Visual Basic. C# is a simple, modern, object-oriented, and type-safe programming language. F# is a cross-platform, open-source, functional programming language for .NET. It also includes object-oriented and imperative programming. Visual Basic is an approachable language with a simple syntax for building type-safe, object-oriented apps. Whether you're working in C#, F#, or Visual Basic, your code will run natively on any compatible OS. Different .NET implementations handle the heavy lifting for you.
    Downloads: 24 This Week
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  • 12
    Obfuscar

    Obfuscar

    Open source obfuscation tool for .NET assemblies

    Obfuscar is an open-source .NET obfuscator released under MIT license. It provides basic obfuscation features that help secure secrets in a .NET assembly. An obfuscation tool designed for most .NET developers. Hide everything private, while keep everything public. You can achieve such simply via default settings. Hide class/method/property/event names that you don't want to expose. This is irreversible. String contents can be compressed so that end users won't easily learn them. However, this is reversible by certain tools.
    Downloads: 24 This Week
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  • 13
    dotnet sdk

    dotnet sdk

    Core functionality needed to create .NET Core projects

    Core functionality needed to create .NET Core projects, that is shared between Visual Studio and CLI. There are no fees or licensing costs, including for commercial use. .NET is open-source and cross-platform, with free development tools for Windows, Linux, and macOS. .NET is supported by Microsoft. Microsoft ships official releases that are built and tested on Microsoft-maintained servers in Azure and supported just like any Microsoft product. .NET is open source and we are very thankful for the many contributions it receives from the community. To test your locally built SDK, run eng\dogfood.cmd after building. That script starts a new Powershell with the environment configured to redirect SDK resolution to your build.
    Downloads: 16 This Week
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  • 14
    reacTIVision
    reacTIVision is a computer vision framework for the fast and robust tracking of markers attached on physical objects, and the creation of multi-touch surfaces. It was designed for the rapid development of table-based tangible user interfaces.
    Downloads: 74 This Week
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  • 15
    File system/directory monitoring utilities with loggin and task processing support (can execute files or make a WCF service call). Multiple configuration options. Source code libraries can be used to create a custom file system monitor.
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    Downloads: 79 This Week
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  • 16
    MSI Downloader

    MSI Downloader

    MSI installers for a wide range of software and utilities

    MSI Downloader has been created for IT professionals who want a quick and easy method of downloading the latest MSI installers for various software. MSI installers are much easier to use for deployment using systems like Group Policy, Microsoft Deployment Toolkit (MDT) and Microsoft System Center Configuration Manager (SCCM). Some publishers happily supply MSI installers for their software, however, some are very hard to find. So this new tool will not only be providing the easy to find MSI installers, but also the hard to find ones and in some cases, the impossible to find ones - ones where we will create the MSI installers for them! The aim to keep all the MSI Installers within our utility fully up to date, but if you find something that is not, please let us know and we will correct it.
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    Downloads: 194 This Week
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  • 17
    reko

    reko

    Reko is a binary decompiler

    Reko (Swedish: "decent, obliging") is a decompiler for machine code binaries. This project is freely available under the GNU General Public License. The project consists of front ends, core decompiler engine, and back ends to help it achieve its goals. A command line, a Windows GUI, and a ASP.NET front end exist at the time of writing. The decompiler engine receives inputs from the front ends in the form of either individual executable files or decompiler project files. Reko project files contain additional information about a binary file, helpful to the decompilation process or for formatting the output. The decompiler engine then proceeds to analyze the input binary. Reko has the ambition of supporting decompilation of various processor architectures and executable file formats with minimal user intervention. For a complete list, see the supported binaries page.
    Downloads: 13 This Week
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  • 18
    Json.NET

    Json.NET

    A popular high-performance JSON framework for .NET

    Serialize and deserialize any .NET object with Json.NET's powerful JSON serializer. Create, parse, query and modify JSON using Json.NET's JObject, JArray and JValue objects. Query JSON with an XPath-like syntax. 50% faster than DataContractJsonSerializer, and 250% faster than JavaScriptSerializer. Json.NET makes the simple easy and the complex possible. If you need it, Json.NET supports converting between XML and JSON. Json.NET is open source software and is completely free for commercial use. Json.NET supports Windows, MacOS, Linux, Mono, and Xamarin. Over 1 billion downloads and counting, Json.NET is the number one library on NuGet. Json.NET documentation is the first place to go for help. It includes over 100 code samples. Json.NET is open source under the MIT license and is free for commercial use.
    Downloads: 12 This Week
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  • 19
    Clean Architecture

    Clean Architecture

    Clean Architecture Solution Template

    A starting point for Clean Architecture with ASP.NET Core. Clean Architecture is just the latest in a series of names for the same loosely-coupled, dependency-inverted architecture. You will also find it named hexagonal, ports-and-adapters, or onion architecture. This architecture is used in the DDD Fundamentals course by Steve Smith and Julie Lerman. Contact Steve's company, NimblePros, for Clean Architecture or DDD training and/or implementation assistance for your team. After installing the template, you should be able to create a new project in Visual Studio and search for Clean Architecture. You should see the template appear in your list of project templates. Note that the template is generally only updated with major updates to the project. The GitHub repository will always have the latest bug fixes and enhancements.
    Downloads: 11 This Week
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  • 20
    IKVM.NET is a JVM for the Microsoft .NET Framework and Mono. It can both dynamically run Java classes and can be used to convert Java jars into .NET assemblies. It also includes a port of the OpenJDK class libraries to .NET.
    Downloads: 41 This Week
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  • 21
    GitVersion

    GitVersion

    From git log to SemVer in no time

    GitVersion is free to use, improve, contribute and distribute. Source code is available on GitHub under MIT license. GitVersion is built for many different use-cases and workflows, so whether you use Mainline, Git Flow or GitHub Flow, GitVersion has you covered. Gitversion is highly configurable and can be made to support your specific versioning scheme, almost regardless of what it may be. Expose version variables in different formats to the tools you use. Use GitVersion locally or in a build pipeline with TeamCity, AppVeyor, Jenkins or any of the other supported build servers. GitVersion is a tool that generates a Semantic Version number based on your Git history. The version number generated from GitVersion can then be used for various different purposes. GitVersion can be used in a Continuous Server pipeline to generate a version number that both labels the build itself and makes the different version variables available to the rest of the build pipeline.
    Downloads: 8 This Week
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  • 22
    Seal Report

    Seal Report

    Database Reporting Tool and Tasks (.Net)

    Seal Report is an open-source tool for the generation of daily reports from any database. It offers a complete framework for producing dynamic reports and dashboards, with a focus on simplicity and ease of use.
    Downloads: 8 This Week
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  • 23
    Xamarin.iOS & Xamarin.Mac

    Xamarin.iOS & Xamarin.Mac

    Bridges the worlds of .NET with the native APIs of macOS, iOS, tvOS

    Bridges the worlds of .NET with the native APIs of macOS, iOS, tvOS, and watchOS. This module is the main repository for both Xamarin.iOS and Xamarin.Mac. These SDKs allow us to create native iOS, tvOS, watchOS and macOS applications using the same UI controls we would in Objective-C and Xcode, except with the flexibility and elegance of a modern language (C#), the power of the .NET Base Class Library (BCL), and two first-class IDEs—Visual Studio for Mac and Visual Studio—at our fingertips. This repository is where we do development for the Xamarin.iOS and Xamarin.Mac SDKs. The preferred method for installing Xamarin.iOS and Mac is to use the Visual Studio installers (Windows, Mac). The team also strongly recommends using the latest Xamarin SDK and Xcode whenever possible.
    Downloads: 8 This Week
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  • 24
    taskt

    taskt

    Free and open-source robotic process automation (rpa)

    taskt (formerly sharpRPA) is the first truly free, easy-to-use, and open-source process automation client built on the .NET Framework in C#. taskt allows you to build and design process automation without needing to write application code. taskt allows you to automate the boring stuff and create efficienies by giving you the power to craft a digital workforce that executes and performs rule-based automation. No API? No Problem! Included is a "what you see is what you get" bot designer with dozens of automation commands. An element recorder and screen recorder is also included that can record and replay scripted automation. taskt works by allowing a bot developer to design a bot configuration known as a script. The bot configuration is then intepreted by a script engine at run-time and executes against the bot developer's selected parameter inputs. Each command contains the definitions for the required inputs as well as the required logic at run-time.
    Downloads: 8 This Week
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  • 25
    MahApps.Metro

    MahApps.Metro

    Cobble together a better UI for their own WPF applications

    MahApps.Metro is a framework that allows developers to cobble together a Metro or Modern UI for their own WPF applications with minimal effort. MahApps.Metro overrides the default style of all common WPF controls and gives them a modern look. MahApps.Metro also includes some custom controls based on concepts from Windows Phone, Windows 8 and Window 10 (UWP) Apps. You can install MahApps.Metro via the NuGet UI or with the Package Manager Console. If you want to use a pre-release packages of MahApps.Metro, you need to enable Include Prerelease in the NuGet UI. All resources of MahApp.Metro are located within separate resource dictionaries. To adopt the MahApps.Metro theme, you will need to add the resource dictionaries to your App.xaml. To start with the full MahApps styling and full window support you need to change your normal Window to our MetroWindow.
    Downloads: 7 This Week
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