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

  • The Most Powerful Software Platform for EHSQ and ESG Management Icon
    The Most Powerful Software Platform for EHSQ and ESG Management

    Addresses the needs of small businesses and large global organizations with thousands of users in multiple locations.

    Choose from a complete set of software solutions across EHSQ that address all aspects of top performing Environmental, Health and Safety, and Quality management programs.
    Learn More
  • Collect! is a highly configurable debt collection software Icon
    Collect! is a highly configurable debt collection software

    Everything that matters to debt collection, all in one solution.

    The flexible & scalable debt collection software built to automate your workflow. From startup to enterprise, we have the solution for you.
    Learn More
  • 1
    CppSharp

    CppSharp

    Tools and libraries to glue C/C++ APIs to high-level languages

    CppSharp is a tool and set of libraries that facilitates the usage of native C/C++ code with the .NET ecosystem. It consumes C/C++ header and library files and generates the necessary glue code to surface the native API as a managed API. Such an API can be used to consume an existing native library in your managed code or add managed scripting support to a native codebase. The supported target languages at present are C# and C++/CLI. It can also be used as a library to parse native code into a syntax tree with a rich declaration and type information model. Generates the glue binding code from a syntax tree of the native code. Provides APIs for parsing of C/C++ source code into a syntax tree. Mirrors the Clang's C/C++ AST and type system classes in C# APIs.
    Downloads: 2 This Week
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  • 2
    Hymnal Xamarin

    Hymnal Xamarin

    New version of the adventist hymnal multi-platform and multi-language

    Hymnal Xamarin is an open-source Xamarin application for accessing hymnals, providing a simple and intuitive interface for worship.
    Downloads: 2 This Week
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  • 3
    LiteNetLib 1.0 indev

    LiteNetLib 1.0 indev

    Lite reliable UDP library for Mono and .NET

    Lite reliable UDP library for .NET Framework 3.5, Mono, .NET Core 2.0, .NET Standard 2.0. Small packet size overhead (1 byte for unreliable, 3 bytes for reliable packets). Helper classes for sending and reading messages. Always use library sources instead of precompiled DLL files (because there are platform-specific #ifdefs and workarounds for unity bugs). Fast packet serializer (Usage manual). Automatic small packets merging. Automatic fragmentation of reliable packets. Automatic MTU detection. UDP NAT hole punching. NTP time requests. Packet loss and latency simulation. IPv6 support (dual mode). Connection statisitcs (need DEBUG or STATS_ENABLED flag). Multicasting (for discovering hosts in local network). Unity support.
    Downloads: 2 This Week
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  • 4
    MahApps.Metro IconPacks

    MahApps.Metro IconPacks

    Awesome icon packs for WPF and UWP in one library

    Awesome icon packs for WPF and UWP in one library.
    Downloads: 2 This Week
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  • Failed Payment Recovery for Subscription Businesses Icon
    Failed Payment Recovery for Subscription Businesses

    For subscription companies searching for a failed payment recovery solution to grow revenue, and retain customers.

    FlexPay’s innovative platform uses multiple technologies to achieve the highest number of retained customers, resulting in reduced involuntary churn, longer life span after recovery, and higher revenue. Leading brands like LegalZoom, Hooked on Phonics, and ClinicSense trust FlexPay to recover failed payments, reduce churn, and increase customer lifetime value.
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  • 5
    OxyPlot

    OxyPlot

    A cross-platform plotting library for .NET

    OxyPlot is a cross-platform plotting library for .NET. The code is licensed under the MIT license. This is a very permissive and corporate-friendly license. See open source and tl;dr for more details. The core library is a Portable Class Library that can be used on different platforms. Custom controls are implemented for WPF, Windows 8, Windows Phone, Windows Phone Silverlight, Windows Forms, Silverlight, GTK#, Xwt, Xamarin.iOS, Xamarin.Android, Xamarin.Forms and Xamarin.Mac. OxyPlot contains many different types of axes and series. If you need some functionality that is not included in the library, you can also create a derived class and override the rendering implementation. Make sure you reference and initialize the OxyPlot platform renderers, otherwise you will see nothing. The latest pre-release packages are pushed by AppVeyor CI to myget.org. To install these packages, set the myget.org package source https://www.myget.org/F/oxyplot and remember the "-pre" flag.
    Downloads: 2 This Week
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  • 6
    Simple Network Management Protocol (SNMP) .Net library written in C# (csharp). Implements protocol version 1, 2 and 3
    Downloads: 9 This Week
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  • 7
    WebKit .NET
    WebKit .NET is a control library wrapper for WebKit written in C#. The aim is to make it easy for users to incorporate WebKit into their .NET applications.
    Downloads: 6 This Week
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  • 8
    sharpPDF is easy-to-use c# library to generate PDF on the fly. It allows to save pdf files or get binary streams in output(for example, usable in ASP.NET).
    Downloads: 12 This Week
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  • 9
    Cecil

    Cecil

    Cecil is a library to inspect, modify and create .NET programs

    Cecil is a library to inspect, modify and create .NET programs and libraries. Mono.Cecil is a library to generate and inspect programs and libraries in the ECMA CIL form. Analyze .NET binaries using a simple and powerful object model, without having to load assemblies to use Reflection. Modify .NET binaries, add new metadata structures and alter the IL code. Cecil has been around since 2004 and is widely used in the .NET community. If you're using Cecil, or depend on a framework, project, or product using it, please consider sponsoring Cecil. Cecil 0.10 beta 5 addresses a long standing issue: previously, a rewrite of native pdb files would lose some debugging information, including the list of namespaces that were used in methods (and thus breaking the expression evaluation) or the scopes in generators (for iterators or async methods).
    Downloads: 1 This Week
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  • Skillfully - The future of skills based hiring Icon
    Skillfully - The future of skills based hiring

    Realistic Workplace Simulations that Show Applicant Skills in Action

    Skillfully transforms hiring through AI-powered skill simulations that show you how candidates actually perform before you hire them. Our platform helps companies cut through AI-generated resumes and rehearsed interviews by validating real capabilities in action. Through dynamic job specific simulations and skill-based assessments, companies like Bloomberg and McKinsey have cut screening time by 50% while dramatically improving hire quality.
    Learn More
  • 10
    Going.Plaid

    Going.Plaid

    Plaid API .NET library

    Going.Plaid is a library for interacting with Plaid's banking APIs. See their documentation here. It is supported for .net standard 2.0, .net core 3.1, and .net 5.0+.
    Downloads: 1 This Week
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  • 11
    NSubstitute

    NSubstitute

    A friendly substitute for .NET mocking libraries

    NSubstitute is designed for Arrange-Act-Assert (AAA) testing, so you just need to arrange how it should work, then assert it received the calls you expected once you're done. Because you've got more important code to write than whether you need a mock or a stub. It is an attempt to satisfy our craving for a mocking library with a succinct syntax that helps us keep the focus on the intention of our tests, rather than on the configuration of our test doubles. We've tried to make the most frequently required operations obvious and easy to use, keeping less usual scenarios discoverable and accessible, and all the while maintaining as much natural language as possible. There are already some great mocking libraries around for .NET, so why create another? We found that for all their great features, none of the existing libraries had the succinct syntax we were craving — the code required to configure test doubles quickly obscured the intention behind our tests.
    Downloads: 1 This Week
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  • 12
    Spectre.Console

    Spectre.Console

    Library that makes it easier to create beautiful console applications

    Spectre.Console is a .NET library that enables the creation of rich, cross‑platform console applications. Heavily inspired by Python’s Rich library, it provides advanced styling, layout, and input capabilities for modern terminal UIs. Supports tables, grids, panels, and a Rich inspired markup language. Supports the most common SRG parameters when it comes to text styling such as bold, dim, italic, underline, strikethrough, and blinking text. Supports 3/4/8/24-bit colors in the terminal. The library will detect the capabilities of the current terminal and downgrade colors as needed. Written with unit testing in mind.
    Downloads: 1 This Week
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  • 13
    eShopOnWeb

    eShopOnWeb

    Sample ASP.NET Core 8.0 reference application

    eShopOnWeb is Microsoft's .NET core sample reference application demonstrating monolithic web app architecture using Clean Architecture principles. It illustrates modern .NET patterns, organized across projects, and is designed for learning and as a starter template. The eShopOnWeb sample is related to the eShopOnContainers sample application which, in that case, focuses on a microservices/containers-based application architecture. However, eShopOnWeb is much simpler in regards to its current functionality and focuses on traditional Web Application Development with a single deployment.
    Downloads: 1 This Week
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  • 14
    iText Core/Community

    iText Core/Community

    iText for .NET is the .NET version of the iText library

    iText Core/Community (previously known as iTextSharp) is a high-performance, battle-tested library that allows you to create, adapt, inspect, and maintain PDF documents, allowing you to add PDF functionality to your software projects with ease. It is also available for Java. For more advanced examples, refer to our Knowledge Base or the main Examples repo. You can find C# equivalents to the Java Signing examples here, though the Java code is very similar since they have the same API. Some of the output PDF files will be incorrectly displayed by the GitHub previewer, so be sure to download them to see the correct results. The iText Suite builds on over a decade of lessons learned from iText 5 (and iTextSharp) development. The latest release of iText, version 8, is a simpler, more performant and extensible library that is ready to handle the increased challenges of today's document workflows, one add-on at a time.
    Downloads: 1 This Week
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  • 15
    Fast Artificial Neural Network Library is a free open source neural network library, which implements multilayer artificial neural networks in C with support for both fully connected and sparsely connected networks. Cross-platform execution in both fixed and floating point are supported. It includes a framework for easy handling of training data sets. It is easy to use, versatile, well documented, and fast. Bindings to more than 15 programming languages are available. An easy to read introduction article and a reference manual accompanies the library with examples and recommendations on how to use the library. Several graphical user interfaces are also available for the library.
    Downloads: 6 This Week
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  • 16
    APTools
    APTools (Accelerate Programming Tools) is a .NET libraries that aim to provide common needed objects and functions and therefore accelerate programming. Its brings immutable collections, parameter validation, design patterns interfaces and more.
    Downloads: 17 This Week
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  • 17
    AL-IV

    AL-IV

    ALFOUR Programming language. Simple, safe, power, multi-platform.

    A programming language AL-IV (ALFOUR) is a high-level imperative object oriented programming language with minimal introduction level, easy porting to any platform claiming a very high level of safety and stability, with a controllable level of code protection, high efficiency of an executable code, full independence from a target platform, minimal enter level.
    Downloads: 16 This Week
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  • 18
    Coronis SDK

    Coronis SDK

    Set of module for data processing of wireless device

    The goal is to create a leading “Set of software libraries for data processing of wireless device based on Coronis platform“. These libraries will run on all major platforms (embedded and desktop) and provide services for data processing through generic APIs. Keywords: Coronis, Wavenis, API, Plugin, Wireless, Waveport, Wavecard, Profile, Java, C, C++, C#
    Downloads: 4 This Week
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  • 19
    rsptar_gzip

    rsptar_gzip

    TAR based DLL

    C code and DLL (with sample project) with library libarchive and GNU tar 1.34 to list, update, delete, extract and create latest GNU tar files uncompressed or compressed with gzip, gzip2, gzip2 multi-thread, bzip2, bzip3, bzip3 multi-thread, lzip, lzop, lzop2, lzop2 multi-thread, lz4, lz5 multi-thread, lzma, brotli, brotli2 multi-thread, Zstandard, xz , the old Unix compression utility 'compress' (.Z) , compress2 multi-thread (.Z2), zip, 7zip and many more formats with full Unicode support when creating and extracting files in windows, compiled with mingw, notice that we have developed a replacement for tar when running in windows with support to file attributes, it is extensible without breaking compatibility with older files, this means that if in the future we add new features to the format it still will be able to extract older VAL files, this is the recommended mode to be used, the extension is .val, support to AES 256, RC4, Serpent, MARS, RC6 and TWOFISH encryption
    Downloads: 14 This Week
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  • 20
    RSPpmp3

    RSPpmp3

    multi-media player updated yearly

    Win64/Win32 DLL and C# sample project (soon C project too (possible)) to play all audio and video files that are supported by Libav library (this release is using the new Libav libraries available (14/nov/2022)), also now a stripped version with only standard audio (Mp3, Ogg, AAC, Opus), is available, it is marked as no Libav version Also after 25/nov/2024 some of the wav effects are being converted to Edge plugins, with the valuable help of Copilot, the license of the plugins is MIT With the help of Microsoft Copilot we are adding Lucid Mode video enhancement
    Downloads: 6 This Week
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  • 21
    DSP Lab

    DSP Lab

    Digital Signal Processing Simulation

    DSP Lab is a digital signal processing simulation application created to simulate and visualize process of sampling and filtering analog signal using DSP system. This application is created to provide as a tool for educator and student to visualize and understand DSP system. Source code is available at https://payhip.com/b/9mPY
    Downloads: 10 This Week
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  • 22
    Voikko

    Voikko

    Library of linguistic tools

    Voikko is a spell checking, grammar checking, morphological analysis and hyphenation system. Spell checkers are available for multiple languages, other features for Finnish only.
    Downloads: 9 This Week
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  • 23

    OpenGL4Net

    Simple OpenGL 4.3 wrapper for .NET platform

    Feb. 2014: The project is still active; a new version with many changes is comming soon! NOTE: The Khronos group made a big shift in describing the OpenGL specification. Starting from OpenGL 4.4, the old .spec files are replaced by .xml which is great news for community, bad news for me and this project as it strongly depends on the old format. Currently I am working on the new version, but there's really a huge change, so please, be patient. I'd also would like to make the licensing clear (probably BSD). OpenGL4Net is a simple wrapper of OpenGL 4.3 for .NET platform. The main idea of the library is to keep the syntax as close as possible to the C style and on the other hand, provide some overloaded functions that simplifies the development of .NET application. The library also contains some helper classes to make a development really fast (e.g., class RenderContext for opening the OpenGL context; or class Program for loading, compiling and linking shaders)
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    Downloads: 5 This Week
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  • 24
    .Net Runtime Library for Delphi

    .Net Runtime Library for Delphi

    This is the best library to work with the .Net framework from Delphi.

    The .Net Runtime Library for Delphi (CNClrLibrary) is the best library to work with .Net framework and .Net libraries from Delphi. It is designed to provide a way to interact with applications written in anyone of the .Net languages (such as C#, Visual Basic.Net, Delphi.Net, JScript.Net, etc) from Delphi. CNClrLibrary allows Delphi to use .Net libraries without the need for registry entries, COM registrations, or changes to the .NET libraries. Competitive Advantages: - No extra dll is required when deployed. - No COM registration of .Net Libraries is required when deployed. - There are tools to generate your .Net Libraries into Delphi pas files. - Allows Delphi to consume .Net libraries as if they were native code. - Full access to .Net Framework Class Library. - Easy to use. CNClrLibrary can do so much: - Access .Net Framework Class Library. - Access Third Party .Net Libraries. - Access Your .Net Libraries. - etc Latest Version: 6.0.7.0
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    Downloads: 7 This Week
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  • 25

    ULS

    A lexical analyzer generator that makes the class source code.

    ULS is a class library for creating lexical analyzer from language specification file. It's provided as C/C++/C# and Java (class) libraries with a few of tools on Linux/Windows platform.
    Downloads: 8 This Week
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