What Is the DHT22 (AM2302)? Temperature and Humidity Sensor and Uses
The DHT22 (AM2302) is the more capable version of the DHT11: a digital sensor that measures temperature (−40…80 °C, ±0.5 °C) and humidity (0–100 %, ±2–5 %) over a single wire. It also measures negative temperatures and the full humidity range; sampling is ~0.5 Hz. It is preferred for more accurate climate monitoring.
The DHT22 (AM2302) is the more capable sibling of the DHT11: a digital sensor that measures temperature and humidity over a wider range with higher accuracy. For the concept, see what is a humidity sensor.
What is the DHT22 used for?
More accurate ambient/climate monitoring, weather stations, greenhouse and HVAC projects. It works on the same single-wire logic as the DHT11 but also measures negative temperatures and the full humidity range.
Highlights
| Parameter | Value |
|---|---|
| Temperature | −40 … +80 °C, ±0.5 °C |
| Humidity | 0 – 100 % RH, ±2–5 % |
| Sampling | ~0.5 Hz (once per 2 seconds) |
| Supply | 3.3 – 6 V |
| Interface | Single wire (proprietary digital protocol) |
Limitations
- Slow (~0.5 Hz); not for fast sampling.
- For lab-grade accuracy, I2C sensors (SHT31) are better.
- A pull-up on the data line is recommended.
Equivalents and alternatives
- DHT11: cheaper, narrower range.
- AM2302: the wired/board version of the DHT22.
- SHT31 / AHT20: accurate I2C sensors.
- BME280: temperature + humidity + pressure.
Find it in our catalog
Use the DHT22 search.