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

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  • 1
    mRemoteNG

    mRemoteNG

    mRemoteNG is the next generation of mRemote, open source

    mRemoteNG ("Multi‑Remote Next Generation") is a free, open‑source, tabbed remote connection manager for Windows. It consolidates multiple remote protocols (e.g., RDP, VNC, SSH) into a single interface, making it easier to organize and manage connections. Tabbed interface for keeping multiple sessions organized. Integrates with external credential vaults (e.g. Thycotic Secret Server) and supports dynamic host update for EC2. Supports a wide range of protocols: RDP, VNC, SSH, Telnet, HTTP/HTTPS, raw socket, PowerShell remoting.
    Downloads: 1,743 This Week
    Last Update:
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  • 2
    AssetStudio

    AssetStudio

    AssetStudio is a tool for exploring, extracting and exporting assets

    AssetStudio is a cross-platform tool for exploring, extracting, and exporting assets from Unity games—supporting assetbundles and built-in assets. It handles textures, sprites, audio, meshes, shaders, and more, exporting to formats like png, bmp, mp3, wav. The original is archived (supports Unity ≤2022.1); forks like AssetStudio2024 add support for newer Unity versions and Lua asset decompiling.
    Downloads: 1,287 This Week
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  • 3
    Playnite

    Playnite

    Video game library manager with support for wide range of libraries

    Link games from Steam, Epic, Origin, GOG, Battle.net, Ubisoft Connect and other services, including games that are not installed! Playnite supports a wide variety of console emulators. Playnite's look can be fully customized, from simple color changes to complete layout re-designs. Playnite's functionality can be extended with plugins and script extensions. Fullscreen mode with full controller support is available. Playnite tracks your time in-game (any game including emulated ones). Playnite's user interface is fast and light on resources, even with large libraries. Playnite can run from portable storage without the need of installing system dependencies. No Playnite features are locked behind a paywall and the complete source code is available under the MIT license. Playnite doesn't store any user information on remote servers. All information about your library is stored locally on your PC.
    Downloads: 82 This Week
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  • 4
    LibUsbDotNet C# USB Library
    .NET C# USB library for WinUSB, LibUsb-Win32, and libusb-1.0. Using the common device classes, applications work with all operating systems and drivers without modification. Lots of example code. Open source software at sourceforge.net.
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    Downloads: 179 This Week
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  • 5
    [OFFICIAL] tinyfiledialogs C C++ v3.21.3

    [OFFICIAL] tinyfiledialogs C C++ v3.21.3

    inputbox password WIN OSX GTK QT Console VCPKG C# Lua R Fortran Pascal

    one C/C++ file & header ==> 8 functions: - beep - tray notify popup - message & question - input & password - save file - open file(s) - select folder - color picker complements OpenGL Vulkan GLFW GLUT GLUI VTK SFML TGUI SDL Ogre Unity3d ION OpenCV CeGui MathGL GLM CPW GLOW Open3D ImGui MyGui GLT NGL STB Nuklear Fenster MicroUi & head-less programs NO INIT NO MAIN LOOP NO LINKING NO INCLUDE win (XP to 11) ASCII MBCS UTF-8 UTF-16 (wchar_t) - native dialogs osx/unix ASCII UTF-8 - applescript kdialog zenity shanty … ° SSH console / X forwarding / waypipe Wayland ° the dialogs can be forced into console mode ° curses dialogs via Dialog.exe/Dialog (disabled by default) C89/C23 & C++98/C++23 compliant VisualStudio MinGW GCC Clang TinyCC IntelCC OWCC BCC SunCC on Windows Mac Linux Bsd Solaris Minix Raspbian Flatpak Haiku bindings: VCPKG C# R Lua Rust Haskell Java AllegroBasic Fortran Pascal D JavaScript Kotlin click tab 'Files' for prototypes
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    Downloads: 158 This Week
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  • 6
    QRCoder

    QRCoder

    A pure C# Open Source QR Code implementation

    QRCoder is a simple library, written in C#.NET, which enables you to create QR codes. It hasn't any dependencies on other libraries and is available as .NET Framework and .NET Core PCL version on NuGet. Feel free to grab-up/fork the project and make it better! QRCoder is a .NET library, completely written in C#, which enables you to generate QR Codes as defined by ISO/IEC 18004. The main target of the QRCoder library is to deliver a small and easy-to-use solution, which has no dependencies to other libraries or network stacks. (Like QR Code generators which are relying on online services which makes them vulnerable/slow in some cases.) Although simplicity is one of the main goals, QRCoder is really flexible, in both "output formats" as well as in "payload types". Payload types? Yes, QRCoder brings its own "payload generator", which helps you to create a big list of different payload types to generate special QR codes like "WiFi QR Codes", "Girocodes", "SwissQRCodes" and many more.
    Downloads: 23 This Week
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  • 7
    Windows UI Library

    Windows UI Library

    Windows 10 native controls and Fluent styles for your applications

    WinUI is a user interface layer that contains modern controls and styles for building Windows apps. As the native UI layer in Windows it embodies Fluent Design, giving each Windows app the polished feel that customers expect. WinUI 2 is a library of controls that provides official native Microsoft UI controls and features for Windows UWP apps. WinUI 2 can be used in any Windows 10 UWP XAML app, or in a Xamarin.Forms app running on Windows 10 using native view embedding. WinUI 3 is the next generation of the WinUI framework. It dramatically expands WinUI into a full UX framework, making WinUI available for all types of Windows apps, from Win32 to UWP, for use as the UI layer. You can build new Windows apps using WinUI 3, which ships as a part of the Windows App SDK. The latest available stable release is the Windows App SDK 0.8 (previously called Project Reunion). With this release, you can ship production Desktop apps to the Microsoft Store.
    Downloads: 9 This Week
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  • 8
    Apache log4net

    Apache log4net

    Apache Log4net is a versatile, feature-rich, efficient logging API

    The Apache log4net library is a tool to help the programmer output log statements to a variety of output targets. log4net is a port of the excellent Apache log4j™ framework to the Microsoft® .NET runtime. We have kept the framework similar in spirit to the original log4j while taking advantage of new features in the .NET runtime. The log4net framework is based on Apache log4j™, The log4net framework, source code, binaries, documentation, examples and related materials are published under the terms of the Apache License. This document is an introduction to the log4net API, its unique features and design rationale. Log4net is an open source project based on the work of many authors. It allows the developer to control which log statements are output with arbitrary granularity. It is fully configurable at runtime using external configuration files.
    Downloads: 6 This Week
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  • 9
    Discord Rich Presence

    Discord Rich Presence

    C# custom implementation for Discord Rich Presence

    This is a C# implementation of the Discord RPC library which was originally written in C++. This avoids having to use the official C++ and instead provides a managed way of using the Rich Presence within the .NET environment. While the official C++ library has been deprecated, this library has continued support and development for all your Rich Presence needs, without requiring the Game SDK.
    Downloads: 6 This Week
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  • 10
    MQTTnet

    MQTTnet

    High performance .NET library for MQTT based communication

    MQTTnet is a high-performance .NET library for MQTT-based communication. It provides an MQTT client and an MQTT server (broker) and supports the MQTT protocol up to version 5. TLS support for client and server (but not UWP servers). Extensible communication channels (e.g. In-Memory, TCP, TCP+TLS, WS). Lightweight (only the low-level implementation of MQTT, no overhead). Performance optimized (processing ~150.000 messages/second). Uniform API across all supported versions of the MQTT protocol. Tested on the local machine (Intel i7 8700K) with MQTTnet client and server running in the same process using the TCP channel. The app for verification is part of this repository and stored in /Tests/MQTTnet.TestApp.NetCore. List of connected clients available. Supports connected clients with different protocol versions at the same time. Able to publish its own messages (no loopback client required). Able to receive every message (no loopback client required).
    Downloads: 6 This Week
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  • 11
    PdfPig

    PdfPig

    Read and extract text and other content from PDFs in C#

    This project allows users to read and extract text and other content from PDF files. In addition the library can be used to create simple PDF documents containing text and geometrical shapes.
    Downloads: 6 This Week
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  • 12
    Importer library to import assets from different common 3D file formats such as Collada, Blend, Obj, X, 3DS, LWO, MD5, MD2, MD3, MDL, MS3D and a lot of other formats. The data is stored in an own in-memory data-format, which can be easily processed. www.open3mod.com/ is a 3D model viewer and exporter based on Assimp that is also Open Source.
    Downloads: 26 This Week
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  • 13
    BooruSharp

    BooruSharp

    A C# library to browse Booru websites

    BooruSharp is a C# library designed to simplify interaction with booru-style imageboard websites by providing a unified API for retrieving and managing image data across multiple platforms. It abstracts the differences between various booru implementations such as Danbooru, Gelbooru, and others, allowing developers to query posts, tags, and metadata without needing to handle site-specific logic. The library is distributed via NuGet and integrates seamlessly into .NET applications, making it particularly useful for developers building image browsers, bots, or automation tools. It supports a wide range of booru endpoints and exposes structured methods for accessing posts by ID, tags, or hashes, as well as retrieving random images and metadata. Additionally, BooruSharp includes support for related APIs such as comments, favorites, and tag autocomplete, depending on the target site.
    Downloads: 5 This Week
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  • 14
    XCharts

    XCharts

    A charting and data visualization library for Unity

    A charting and data visualization library for Unity. Unity data visualization chart plugin. A UGUIpowerful, easy-to-use, parameter-configurable data visualization chart plug-in. It supports ten built-in charts. A powerful, easy-to-use, configurable charting and data visualization library for Unity. Visual configuration of parameters, real-time preview of effects, and pure code drawing without additional resources. Support ten built-in charts such as line chart, column chart, pie chart, radar chart, scatter chart, heat map, ring chart, candlestick chart, polar coordinate, parallel coordinate and so on. Supports 3D column charts, funnel charts, pyramids, dashboards, water level charts, pictographic column charts, Gantt charts, rectangular tree charts and other extended charts. Line graphs such as line graphs, curve graphs, area graphs, and stepped line graphs are supported.
    Downloads: 5 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.
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    Downloads: 32 This Week
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  • 16
    FastReport Open Source

    FastReport Open Source

    Free Open Source Reporting tool for .NET

    Free Open Source Reporting tool for .NET Core/.NET Framework that helps your application generate document-like reports.
    Downloads: 71 This Week
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  • 17
    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: 20 This Week
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  • 18
    QuestPDF

    QuestPDF

    A library that can help you with generating PDF documents

    Quickly design and generate PDF documents with an open-source, modern, and battle-tested C# library. Forget about limitations, feel confident, enjoy your task and efficiently deliver professional products. QuestPDF is a progressive library that can help you with generating PDF documents in your .NET application by offering a friendly, discoverable and predictable C# fluent API. Do you believe that creating a complete invoice document can take less than 200 lines of code? We have prepared for you a step-by-step instruction that shows every detail of this implementation and describes the best patterns and practices. This library is created specifically for designing and arranging document layouts, with full paging support. Alternative solutions, such as HTML-based converters, are not designed for this purpose and therefore are often unpredictable and do not produce desired results.
    Downloads: 4 This Week
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  • 19
    iText Community for .NET

    iText Community for .NET

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

    iText for .NET is the .NET version of the iText library, formerly known as iTextSharp, which it replaces. iText represents the next level of SDKs for developers who want to take advantage of the benefits PDF can bring. Equipped with a better document engine, high and low-level programming capabilities and the ability to create, edit, and enhance PDFs.
    Downloads: 4 This Week
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  • 20
    C# SDL
    SDL.NET is a set of object-oriented .NET bindings for the SDL gaming library and provides high-level access to audio, keyboard, mouse, joystick, TTF fonts, various image formats, sound mixing, MPEG-1, and 2D video framebuffer.
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    Downloads: 32 This Week
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  • 21

    ConcatPDF

    PDF Concatenation Tool

    ConcatPDF is the tool to concatenate PDF files. It can concatenate, extract, encrypt, decrypt, configure PDF files, convert image files to PDF. GUI version and CUI version are both available. iText.NET is iText porting on .NET Framework by J#. This library allows you to generate PDF, (X)HTML, XML, RTF files on Microsoft.NET Framework including ASP.NET.
    Downloads: 19 This Week
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  • 22
    This project consists of a linux kernel driver and some user-mode libraries. They allow a process to create a virtual usb host controller. Real or virtual usb devices can be "plugged" into this controller.
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    Downloads: 75 This Week
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  • 23
    C# Algorithms

    C# Algorithms

    Plug-and-play class-library project of standard data structures

    A plug-and-play class-library project of standard Data Structures and Algorithms, written in C#. It contains 75+ Data Structures and Algorithms, designed as Object-Oriented isolated components. Even though this project started for educational purposes, the implemented Data Structures and Algorithms are standard, efficient, stable and tested. This is a C#.NET solution-project, and it contains three subprojects. Algorithms, a class library project which contains the Algorithms implementations. Data Structures, a class library project which contains the Data Structures implementations. Also, UnitTest, a unit-testing project for the Algorithms and Data Structures.
    Downloads: 2 This Week
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  • 24
    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: 2 This Week
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  • 25
    ClashN

    ClashN

    A clash client for Windows, support Mihomo

    clashN is a Windows desktop client for the Clash networking engine, providing a graphical interface to manage proxies, rules, and profiles. It wraps the Clash core in a familiar, configurable UI so users can import subscriptions, switch nodes, and observe connections without editing YAML by hand. The app emphasizes rule-based routing, letting you combine rule providers and policy groups to steer traffic by domain, process, or destination category. System-wide proxy control, including PAC and TUN/TAP options, helps route applications that don’t natively support proxies. Logs, traffic charts, and connection inspectors make troubleshooting and optimization straightforward. For power users, granular profile editing and hot-reloading reduce the friction of iterating on configurations.
    Downloads: 2 This Week
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