Arduino UNO REV 4 Boards

Arduino UNO REV 4 Boards feature two versions, the UNO R4 Wi-Fi® and UNO R4 Minima. The Renesas RA4M1 32-bit Arm® Cortex®-M4 processor powers Arduino UNO REV 4 Boards. These boards offer impressive processing power, memory capacity, and overall functionality. The UNO R4 Wi-Fi incorporates an Espressif S3 Wi-Fi module. The UNO R4 Minima is cost-effective without compromising the microcontroller's core capabilities. The UNO R4 maintains the same form factor, shield compatibility, and 5V operating voltage as the UNO R3.


  • Renesas RA4M1 32-bit Arm Cortex-M4 processor
  • The UNO R4 series offers two versions, the UNO R4 Wi-Fi and the UNO R4 Minima
    • UNO R4 Wi-Fi comes with an Espressif S3 Wi-Fi module in addition to the RA4M1 processor
    • UNO R4 Minima is a cost-effective option for those who prefer the microcontroller without additional features
  • Maintains the same form factor as the UNO R3 with compatibility for existing shields and accessories
  • 5V operating voltage for easy integration with existing projects and components
  • Processor offers enhanced processing capabilities for complex tasks and calculations


  • Internet of Things (IoT)
  • Robotics
  • Home automation
  • Data logging
  • Sensor integration
  • Prototyping and product development
  • Education and learning
  • Art and interactive installations
  • Automation and control systems
  • Wearable technology
  • Environmental monitoring
  • Audio and music projects
  • Internet connectivity and web development
  • Agriculture and farming
  • DIY electronics projects

Compatibility with UNO R3

The UNO R4 maintains the same form factor, pinout, and 5V operating voltage as its predecessor, the UNO R3. Existing shields and projects can be easily ported to the board using the ecosystem for the Arduino UNO. Most libraries are compatible out-of-the-box, while those being ported will be tracked on a web page to inform users about alternatives. 

Shields EcoSystem

Arduino UNO REV 4 Boards


Published: 2023-06-26 | Updated: 2023-09-05