What Is the DHT11? Temperature and Humidity Sensor: Specs and Uses
The DHT11 is a cheap digital sensor that measures temperature and humidity together over a single data line. Temperature 0–50 °C (±2 °C), humidity 20–90 % RH (±5 %), sampling ~1 Hz. It is common in beginner projects; for a wider range/accuracy the DHT22 is preferred. It is read from a single digital pin, no ADC needed.
The DHT11 is a cheap digital sensor that measures temperature and humidity together over a single data line. It is popular with beginners and hobbyists. For the concept, see what is a humidity sensor · what is a temperature sensor.
What is the DHT11 used for?
Ambient temperature/humidity monitoring, simple weather and greenhouse projects. It is read from a single digital pin (a proprietary serial protocol); no ADC is needed. It is cheap but limited in accuracy and speed.
Highlights
| Parameter | Value |
|---|---|
| Temperature | 0 – 50 °C, ±2 °C |
| Humidity | 20 – 90 % RH, ±5 % |
| Sampling | ~1 Hz (once per second) |
| Supply | 3 – 5.5 V |
| Interface | Single wire (proprietary digital protocol) |
DHT11 or DHT22?
The DHT11 is cheap but offers a narrow range and low accuracy. For a wider range and better accuracy, choose the DHT22. Both use a single-wire protocol, but you must select the correct sensor type in the library.
Limitations
- Cannot measure below 0 °C or above 50 °C.
- Slow (~1 Hz) and low accuracy.
- A pull-up (typically 4.7–10 kΩ) on the data line is recommended.
Equivalents and alternatives
- DHT22 (AM2302): wider range and accuracy.
- AHT10 / AHT20 / SHT31: more accurate I2C sensors.
- BME280: temperature + humidity + pressure.
Find it in our catalog
Use the DHT11 search.