Best Free IoT Operating Systems of 2025

Contiki-NG is an open-source and cross-platform operating system that supports Next-Generation IoT devices. It is focused on reliable (secure and reliable) low power communication and standard protocols such as IPv6/6LoWPAN and 6TiSCH, RPL and CoAP. Contiki-NG includes extensive documentation, tutorials and a release cycle. It also has a well-defined development flow to facilitate the seamless integration of community contributions. Contiki-NG source code is distributed under the 3-clause BSD licence, unless otherwise stated. This license grants everyone the right of use and distribution of the code in binary or source format as long as the copyright licence is not lost in the source code.

RT-Thread, short for Real Time-Thread, is an embedded real-time multi-threaded operating system. It has been designed to support multi-tasking, allowing multiple tasks to run simultaneously. Although a processor core can only run one task at a time, RT-Thread executes every task quickly and switches between them rapidly according to priority, creating the illusion of simultaneous task execution. RT-Thread is mainly written in the C programming language, making it easy to understand and port. It applies object-oriented programming methods to real-time system design, resulting in elegant, structured, modular, and highly customizable code. The system comes in a few varieties. The NANO version is a minimal kernel that requires only 3KB of flash and 1.2KB of RAM. For resource-rich IoT devices, RT-Thread can use an online software package management tool, together with system configuration tools, to achieve an intuitive and rapid modular design.

FreeRTOS, which was developed in partnership with some of the world's most renowned chip companies over a 15 year period, is now downloaded every 170 second. It is a market-leading real time operating system (RTOS), for microcontrollers, small microprocessors. FreeRTOS is freely distributed under the MIT open-source license. It includes a kernel as well as a growing number of IoT libraries that can be used across all industries. FreeRTOS is designed with reliability and ease-of-use in mind. The FreeRTOS kernel has been trusted by leading companies around the world as the standard for microcontrollers/small microprocessors. It is known for its reliability, small footprint, and wide device support. You don't need to know how to set up a project. There are pre-configured demos that can be used as templates and IoT reference integrations. You can quickly download, compile, then get to market quicker. Our partner ecosystem offers a variety of options, including professional support and community contributions.

Arm Mbed OS, an open-source IoT operating platform, is free and available for download. It includes all the features needed to create IoT products. The OS contains everything you need for smart, connected products that run on Arm Cortex M based hardware. This includes machine learning capabilities, security stacks, connectivity stacks, and drivers for sensors and other I/O devices. Arm Mbed OS was designed for the Internet of Things. It integrates with connectivity, machine-learning, networking, security stacks, and is supported by software libraries, tutorials, hardware, and examples. Mbed OS supports over 70 silicon, module and cloud partners. This allows you to optimize your developer choice. Mbed OS API allows you to keep your application code clean, portable, and easy while taking advantage security, communications, and machine learning. The integrated solution reduces development time, cost, and risk.

Torizon helps developers be more productive and create products that are easy to maintain. Device monitoring and integrated over-the-air updates allow you to ship faster, fix bugs in the field, deliver new features, and detect problems faster. Software containerization makes maintenance easier and adds an extra layer of robustness. Torizon is continuously validated on Toradex System on Modules. This allows you to focus on your application and not the operating system. Torizon allows you to develop your product in an agile, iterative manner. Remote update capabilities integrate seamlessly with Torizon, making it easy to deploy new software. Device monitoring provides instant feedback on performance and potential issues.