Published October 13, 2025 © MIT

DHT22 Real-Time Data to MySQL Build an IoT Dashboard

Monitor real-time temperature and humidity using DHT22, ESP32, and MySQL with a smart IoT dashboard. Simple IoT project by Yarana IoT Guru

BeginnerFull instructions provided8 hours34

DHT22 Real-Time Data to MySQL Build an IoT Dashboard

Things used in this project

Hardware components

DHT22 Temperature Sensor

Espressif ESP32 Development Board - Developer Edition

Jumper wires (generic)

Software apps and online services

Arduino IDE

Arduino Web Editor

Story

It all started with a simple idea — to create a smart system that could track temperature and humidity in real-time. Using the DHT22 sensor and an ESP32, I built a setup that collects live environmental data and sends it directly to a MySQL database. From there, the data is displayed beautifully on a custom IoT dashboard, allowing users to monitor readings anytime, anywhere.

This project is not just about coding or electronics — it’s about connecting the physical world with the digital one. It shows how simple sensors, when combined with IoT technology, can make daily life smarter and more efficient.

I’ve shared the complete step-by-step tutorial, circuit diagram, and code explanation on my YouTube channel – Yarana IoT Guru, where I create projects that make learning IoT simple and exciting for everyone.

👉 Watch, learn, and build your own IoT dashboard with me — only on Yarana IoT Guru!

Code

Program ESP32 with DHT22

#include 
#include 
#include "DHT.h"

#define DHTPIN 4       // DHT sensor pin
#define DHTTYPE DHT22  // or DHT11 if using DHT11

const char* ssid = "your_wifi_ssid";
const char* password = "your_wifi_password";
const char* serverName = "https://yaranaiotguru.in/tutorial/DHT/insert_data.php";

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  dht.begin();

  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
}

void loop() {
  float temp = dht.readTemperature();
  float hum = dht.readHumidity();

  if (isnan(temp) || isnan(hum)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    http.begin(serverName);
    http.addHeader("Content-Type", "application/x-www-form-urlencoded");

    String postData = "temperature=" + String(temp) + "&humidity=" + String(hum);
    int httpResponseCode = http.POST(postData);

    Serial.print("HTTP Response code: ");
    Serial.println(httpResponseCode);
    Serial.println("Server response: " + http.getString());

    http.end();
  } else {
    Serial.println("WiFi disconnected");
  }
  delay(5000);
}