AHT21 Temperature & Humidity Sensor Module I2C | SHT20

AHT21 High-Precision Digital Temperature & Humidity Sensor Module

The AHT21 Temperature and Humidity Sensor Module delivers fast, accurate environmental readings via I2C communication, making it an ideal upgrade or replacement for the SHT20 and similar sensors. Whether you're building a weather station, a smart home controller, or an IoT data logger, this compact module gives you reliable, calibrated data every time.

Key Features

• High Precision Sensing: Measures both temperature and relative humidity with excellent accuracy for demanding projects.
• I2C Interface: Simple two-wire communication makes integration with Arduino, Raspberry Pi, and other microcontrollers straightforward.
• Drop-in SHT20 Replacement: Fully compatible as a replacement for SHT20-based designs — no major redesign required.
• Resistance Sensor Technology: Utilises a robust resistance-based sensing method for stable, repeatable readings.
• Compact & Lightweight: Small form factor fits easily into enclosures, prototyping boards, or custom PCBs.
• Metal Construction: Durable metal material ensures longevity in a variety of environments.
• Wide Compatibility: Works seamlessly with Arduino, ESP8266, ESP32, STM32, and other I2C-capable platforms.

Specifications

• Model: AHT21
• Communication: I2C
• Sensor Type: Temperature & Humidity (Resistance Sensor)
• Output: Switching Transducer
• Material: Metal
• Customizable: Yes
• Origin: Made in China

What's in the Box

• 1 × AHT21 Temperature & Humidity Sensor Module

Perfect For

• Arduino & microcontroller projects
• Smart home automation systems
• IoT environmental monitoring
• Weather stations & data loggers
• Greenhouse & HVAC control systems
• Industrial sensing applications

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Frequently Asked Questions

Q: Is the AHT21 sensor module compatible with Arduino boards?

A: Yes, the AHT21 temperature and humidity sensor module uses I2C communication, which is fully compatible with Arduino Uno, Nano, Mega, ESP8266, ESP32, and most other I2C-capable microcontroller boards. Simply connect the SDA and SCL pins and use a standard I2C library to get started.

Q: Can the AHT21 module replace an existing SHT20 sensor in my project?

A: Absolutely. The AHT21 is designed as a direct replacement for the SHT20 sensor module. It shares a compatible I2C interface and pinout, meaning minimal or no circuit modifications are needed when upgrading your existing SHT20-based design.

Q: What range of temperature and humidity can the AHT21 module measure?

A: The AHT21 sensor is capable of measuring a wide range of environmental conditions, making it suitable for indoor and outdoor monitoring applications including smart home systems, greenhouses, weather stations, and HVAC control environments.