
Know it
DHT11 is a temperature and humidity sensor so it checks the surrounding area and gives you the results on the Arduino interface or LCD display, depending where youâd like to display the output.
Wire it
Now let's connect the sensor and see how hot will this summer be.
For that, you need the items below:
Jumper Wires
DHT11 temperature and humidity sensor
Arduino board and USB connector

Connections:
Arduino pin GND â DHT11 1st pin from right
Arduino pin 5V â DHT11 1st pin from left
Arduino pin 2 â DHT11 Middle pin
Code it
This is a simple example sketch that reads the temperature and humidity values from the DHT11 sensor, and displays it on the Serial Monitor.
Try it out! Copy the code below:
/*
Measuring the Temperature and Humidity using DHT11
Tutorial link: https://www.learn.voltaat.com/post/dht11
This is an Arduino sketch that reads the temperature and humidity
values from the DHT11 sensor, and displays it on the Serial Monitor.
Components Needed:
1. DHT11 Temperature and humidity sensor ....x1
Connections:
- Arduino pin GND â DHT11 sensor GND pin
- Arduino pin 5V â DHT11 sensor VCC pin
- Arduino pin 2 â DHT11 sensor middle pin
Libraries Needed:
1. DHT.h - Download link:
How to install/use library:
*/
#include "DHT.h" //include this library in the sketch
#define DHTTYPE DHT11 // The type of DHT sensor we are using
DHT dht(DHTPIN, DHTTYPE); // initialize dht sensor
float hum, temp; //variables to read sensor readings
int DHTPIN = 2; // The pin that DHT11 is connected to: Pin 2
// This routine run once
void setup()
{
Serial.begin(9600);
Serial.println(F("DHT11 sensor Starting!")); //write this text on the monitor
dht.begin(); //Start the DHT1 Sensor
}
// This routine loops forever
void loop()
{
delay(2000); // Wait a two seconds between measurements
hum = dht.readHumidity(); // Read humidity value
temp = dht.readTemperature(); // Read temperature value as Celsius (the default)
if (isnan(hum) || isnan(temp) || isnan(tempF)) // Check if any reads failed and exit early (to try again)
{
Serial.println("Failed to read from DHT sensor!"); //if failed to read then write that text on monitor
return; //and start again the loop
}
Serial.print("Humidity: ");
Serial.print(hum); //display humidity value
Serial.println("% Temperature: ");
Serial.print(temp); //display temperature value
Serial.println("°C ");
}