RT-Thread is an open source IoT operating system from China.

Free

Open source IoT Real-Time Operating System (RTOS)

FreeFree tier

Type

Open Source

Founded

2006

Visit Website GitHub (40 stars)

About RT-Thread is an open source IoT operating system from China.

RT-Thread is an open source, neutral, and community-based real-time operating system (RTOS) born in 2006. Primarily written in C, it is designed for IoT devices and embedded systems. The OS applies object-oriented programming methods to real-time system design, resulting in code that is elegant, structured, modular, and highly tailorable. RT-Thread offers two main versions: a Nano version that requires only 3KB Flash and 1.2KB RAM for resource-constrained microcontrollers, and a Standard version for richer IoT devices. The architecture includes a kernel layer with multi-threading, scheduling, semaphores, mailboxes, message queues, memory management, and timers; a components and service layer featuring virtual file systems, FinSH command-line interface, network frameworks, and device frameworks; and a software package ecosystem with 450+ reusable packages. The online software package management tool and system configuration tools enable intuitive and rapid modular customization, supporting complex features like graphical interfaces and smart voice interaction.

Key Features

Open source and community-based RTOS

Written in C, easy to understand and port

Object-oriented design for code elegance and modularity

Nano version: minimum 3KB Flash and 1.2KB RAM

Standard version with rich components and services

Online software package management with 450+ packages

System configuration tools for intuitive modular tailoring

Includes kernel layer, components layer, and software package ecosystem

Supports multi-threading, scheduling, semaphores, mailboxes, message queues, memory management, timers

Components: virtual file systems, FinSH command-line interface, network frameworks, device frameworks

Pros & Cons

Pros

Open source with a strong community and neutral governance
Extremely small footprint for Nano version (3KB Flash/1.2KB RAM)
Rich package ecosystem with over 450 reusable components
Modular and tailorable design allows minimal or feature-rich builds
Easy to port to a wide range of mainstream MCUs and module chips
Online tools simplify package management and system configuration

Best For

Resource-constrained microcontroller (MCU) systemsResource-rich IoT devices requiring graphical interfaces and touch sliding effectsSmart voice interaction applicationsEmbedded systems needing real-time performanceRapid prototyping and development with modular software packages

FAQ

What is RT-Thread?

RT-Thread is an open source, neutral, community-based real-time operating system (RTOS) for IoT devices, born in 2006 and mainly written in C.

What are the memory requirements for the Nano version?

The Nano version requires only 3KB Flash and 1.2KB RAM memory resources.

How many software packages does RT-Thread support?

RT-Thread supports 450+ software packages through its open package platform.

What architectures and chips are supported?

RT-Thread can be quickly ported to a wide range of mainstream MCUs and module chips. Specific architectures are not listed on the main page but the BSP and libcpu directories handle chip migration.

Is RT-Thread suitable for graphical user interfaces?

Yes, for resource-rich IoT devices, RT-Thread can achieve complex functions like Android's graphical interface and touch sliding effects using its components and software packages.