Open Source C# Libraries
Sort By:
C# Libraries
View 75 business solutionsBrowse 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.
-
Build Agents and Models on One PlatformGemini Enterprise Agent Platform is Google Cloud's comprehensive platform for developers to build, scale, govern, and optimize agents and models. Choose from Google's most advanced models and third-party models like Anthropic's Claude Model Family.
-
$300 Free Credits to Build on Google CloudPut your $300 in credit toward real workloads, then keep building with free monthly usage for 20+ products. No commitment and no charge until you upgrade.
-
1
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. -
2
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. -
3
.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.
-
4
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. -
Build Securely on AWS with Proven FrameworksMoving to the cloud brings new challenges. How can you manage a larger attack surface while ensuring great network performance? Turn to Fortinet’s Tested Reference Architectures, blueprints for designing and securing cloud environments built by cybersecurity experts. Learn more and explore use cases in this white paper.
-
5
Windows 11 Guide
Windows Security tools, Encryption, Nextcloud, Graphics, Gaming
Windows 11 Guide is a comprehensive, single-repository handbook for setting up and tuning a Windows 11 (and often Windows 10) desktop for real day-to-day use, covering everything from basic configuration to advanced development and gaming scenarios. It walks users through installing essential applications, configuring Windows security tools, setting up encryption and backups, and integrating productivity services like Nextcloud. The guide also dives into graphics and gaming optimizations, making it useful for both casual users and power users who want better performance and stability. For developers and technical users, it includes sections on virtualization, containers, and Windows Subsystem for Linux (WSL2), showing how to build a capable dev environment on top of Windows. The content is maintained in markdown so it is easy to read on GitHub or convert into other formats like PDF, and it is structured with clear headings so you can jump directly to the section you need. -
6
[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 -
7
OpenAI .NET
The official .NET library for the OpenAI API
OpenAI .NET is the official client library for calling the OpenAI REST API from C# and other .NET languages, with first-class support for modern .NET patterns. It provides strongly typed clients across API areas (chat, audio, images, embeddings, moderations, batches, files, models, vector stores, responses, realtime, assistants) and works with .NET Standard 2.0 while the examples use .NET 8. You install it via NuGet and authenticate with an API key, ideally through environment variables or configuration rather than hardcoding. Every synchronous method has an async counterpart, and the library offers convenient streaming primitives for chat completions so you can process tokens as they arrive. It supports tool/function calling, structured outputs via JSON schema, audio input/output, image generation, embeddings, Whisper transcription, and assistants with retrieval augmented generation. -
8
Polly
A .NET resilience and transient-fault-handling library for policies
Polly is a .NET resilience and transient-fault-handling library that allows developers to express policies such as Retry, Circuit Breaker, Timeout, Bulkhead Isolation, and Fallback in a fluent and thread-safe manner. From version 6.0.1, Polly targets .NET Standard 1.1 and 2.0+. Today's cloud application, mobile, data-streaming, and IoT technologies all depend vitally on reliable connectivity. But underlying systems can fail, and networks are notoriously fickle, outages, latency, transient blips, spikes in load, all challenge 100% reliability. Polly helps you navigate the unreliable network. By providing resilience strategies in fluent-to-express policies such as Retry, WaitAndRetry, and CircuitBreaker, Polly can help you reduce fragility, and keep your systems and customers connected. Example usages are fault-tolerance for any distributed systems and inter-process calls, such as WCF, RESTful calls between microservices, calls to cloud services, Internet of Things connectivity, etc. -
9
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. -
Save Up to 91% on Cloud Compute With Spot VMsRun batch jobs at 60-91% off with Spot VMs. Long-running workloads get automatic discounts with sustained use.
-
10
ASP.NET API Versioning
Libraries which add service API versioning to ASP.NET Web API
ASP.NET API versioning gives you a powerful, but easy-to-use method for adding API versioning semantics to your new and existing REST services built with ASP.NET. The API versioning extensions define simple metadata attributes and conventions that you use to describe which API versions are implemented by your services. You don't need to learn any new routing concepts or change the way you implement your services in ASP.NET today. The default API versioning configuration is compliant with the versioning semantics outlined by the Microsoft REST Guidelines. There are also a number of customization and extension points available to support transitioning services that may not have supported API versioning in the past or supported API versioning with semantics that are different from the Microsoft REST versioning guidelines. -
11
QuickOpen Plugin for notepad++
plugin for notepad++
This plugin mimics the "open selected file" in PSPad. I am a PHP developer and i often see an 'require_once("../this/is/some/file.php");'. In pspad you can select the whole path (../this/is/some/file.php) and open it from the menu. Now you can do the same in notepad++. Just select the whole path and press alt+o, or use the button in the toolbar on top. It will open the file automatically. The plugin understands the relative path. The code is also available on https://bitbucket.org/sgezel/quickopenplugin -
12
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. -
13
PDFsharp
PDFsharp is a .NET library for creating and modifying PDF documents.
PDFsharp moved to https://github.com/empira/PDFsharp PDFsharp is a .NET library for creating and modifying Adobe PDF documents programmatically from any .NET language like C# or VB.NET. PDFsharp defines classes for the objects found in PDF files, so you never have to deal with IDs or references directly. The downloads include MigraDoc Foundation, a .NET library for creating documents on the fly (supports PDF and RTF). PDFsharp is the .NET library that easily creates and processes PDF documents on the fly from any .NET language. The same drawing routines can be used to create PDF documents, draw on the screen, or send output to any printer. MigraDoc Foundation is the .NET library that easily creates documents based on an object model with paragraphs, tables, styles, etc. and renders them into PDF, XPS, or RTF. -
14
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. -
15
Basic Computer Games
An updated version of the classic "Basic Computer Games" book
Basic Computer Games is a modern revitalization of the classic “Basic Computer Games” book’s collection of games, ported and expanded into various modern, memory-safe and scripting languages. It includes illustrative code examples of many classic games (e.g. Blackjack, Bowling) in multiple languages, with the goal of making the historical games accessible and educational in safe modern environments. Definitely use the most recent versions and features of the target language, but also try to keep the code samples simple and explainable – the goal is to teach programming in the target language, not necessarily demonstrate the cleverest one-line tricks, or big system "enterprise" coding techniques designed for thousands of lines of code. -
16
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). -
17
Stripe.net
Stripe.net is a sync/async .NET 4.6.1+ client
A .NET library to facilitate Stripe payment integration, supporting a full range of payment and subscription features for .NET applications. -
18
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.
-
19
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. -
20
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. -
21
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.
-
22
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. -
23
Elsa Workflows
A .NET Standard 2.0 Workflows Library
Build workflows in code using the Workflow Builder API or as data using JSON syntax. Or use the workflow designer to design executable workflows visually. Elsa comes with a reusable dashboard component to manage workflows and activities. Run workflows from within your application using simple to use APIs. Start or resume workflows manually, or automatically by invoking triggers. Make it your own by extending the set of activities with your own. Implementing custom activities allows for powerful workflows that can be implemented with ease. Workflows can be defined using plain C# code. In addition to an increasing number of activities that you can choose from, Elsa is designed to be extensible with your own custom activities. Short-running Workflows can be useful to implement a business rules engine, while long-running workflows greatly simplify the implementation of complex processes that involve coordinating between multiple agents (users & machines). -
24
NetTopologySuite
A .NET GIS solution that is fast and reliable for the .NET platform.
A .NET GIS solution that is fast and reliable for the .NET platform. NetTopologySuite is a direct port of all the functionalities offered by JTS Topology Suite: NTS exposes JTS in a '.NET way', for example using Properties, Indexers, etc. The JTS Topology Suite is an API for modeling and manipulating 2-dimensional linear geometry. It provides numerous geometric predicates and functions. JTS conforms to the Simple Features Specification for SQL published by the Open GIS Consortium. -
25
Pidgin
A lightweight and fast parsing library for C#
Pidgin is a lightweight and fast parser combinator library for C#. It allows developers to construct parsers using a declarative approach, facilitating the creation of complex parsers without external tools.
