Get Started With the DHT11 Humidity and Temperature Sensor

Read the temperature and humidity with DHT11 and Arduino

Written By: Cherie Tan

Dash icon
Difficulty
Easy
Steps icon
Steps
8
Sometimes, you will want to be able to read both the temperature and humidity in your surroundings. 

In this guide, you will learn how to use a DHT11 temperature and humidity sensor with the Arduino. 

Doing so will enable you to progress onto working on further projects such as a greenhouse control device or a DIY weather station.

Step 1 Insert the DHT11 Into the Breadboard

Insert the DHT11 Into the Breadboard

Step 2 Bridge DHT11 Pin 1 and Pin 2 with a 10K Resistor

Bridge DHT11 Pin 1 and Pin 2 with a 10K Resistor.
This resistor will pull up the signal line.

Step 3 Connect Ground to the DHT11

Connect Ground to the DHT11

Step 4 Connect 5V to the DHT11

Connect 5V to the DHT11

Step 5 Connect the DHT11 to Digital Pin 2

Connect the DHT11 to Digital Pin 2

Step 6 Install the SimpleDHT Library

Install the SimpleDHT Library.

Step 7 Upload the code

#include <SimpleDHT.h>

// for DHT11,
//      VCC: 5V or 3V
//      GND: GND
//      DATA: 2
int pinDHT11 = 2;
SimpleDHT11 dht11;

void setup() {
  Serial.begin(9600);
}

void loop() {
  // start working...
  Serial.println("=================================");
  Serial.println("Sample DHT11...");

  // read without samples.
  byte temperature = 0;
  byte humidity = 0;
  int err = SimpleDHTErrSuccess;
  if ((err = dht11.read(pinDHT11, &temperature, &humidity, NULL)) != SimpleDHTErrSuccess) {
    Serial.print("Read DHT11 failed, err="); Serial.println(err);delay(1000);
    return;
  }

  Serial.print("Sample OK: ");
  Serial.print((int)temperature); Serial.print(" *C, ");
  Serial.print((int)humidity); Serial.println(" H");

  // DHT11 sampling rate is 1HZ.
  delay(1500);
}
Upload this code to your Arduino

Step 8 Open the Serial Port

Open your Serial Port and look at the Temperature and Humidity!

Be sure to be using a Baud rate of 9600.
Breath on your Sensor and look at what happens!