ESP8266 with Telegram Messenger for Monitoring Temperature and Humidity using DHT11

(Last Updated On: January 17, 2022)

ESP8266 with Telegram Messenger:

ESP8266 with Telegram

ESP8266 with Telegram Messenger for Monitoring Temperature and Humidity using DHT11- So far, I have been using different IoT Platforms for monitoring different types of sensors and for controlling different types of electrical loads. The most popular IoT platforms that I have been using for quite a long time include the Blynk application, Arduino IoT Cloud, Ubidots, Thingspeak, and Firebase. Just like all these IoT platforms, you can also use Telegram Messenger as an IoT platform for monitoring sensors and for controlling electrical loads. This is my first article on Telegram Messenger and I will try my level best to explain each and every detail so that you can easily understand how to get started with Telegram Messenger. Since this is a getting started tutorial, that’s why I decided to start with the most basic sensor which is the DHT11 Temperature and Humidity Sensor. You can use Telegram Messenger with different controller boards which of course I will cover in my upcoming videos and articles, but for now, I will start with the Nodemcu ESP8266 WiFi Module. Before, I am going to share with you the test results, first, a few words about the sponsor of this project for helping me purchase the required components and tools.

Altium Designer:

altium designer sponsor

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Telegram for Sensor Monitoring:

ESP8266 with Telegram

I powered up my Nodemcu ESP8266 WiFi module using a 12V power supply. I have this 7805 voltage regulator which converts 12 volts into regulated 5 volts.  Next, I opened the Telegram Messenger and then I opened the Tempmonitoringbot.

You can see the previously implemented commands, I have been testing it for a while and it’s working perfectly. You can request the temperature and humidity data from anywhere in the world, all you need is to write the command or simply click on the command and then wait for a few seconds, the reply time depends on the internet speed. In the same way, we can request the temperature value.

Isn’t it cool? You simply create a Bot in Telegram Messenger that hardly takes a minute and then this Bot takes care of all the communications. Anyways, you can see it’s working just perfectly. Now, it’s time to explain the circuit diagram and programming of this IoT-based project using Telegram Messenger, Nodemcu ESP8266, and DHT11 Temperature and Humidity Sensor. Without any further delay, let’s get started!!!

Amazon Links:

DHT11 Temperature and Humidity Module:

Nodemcu ESP8266 WiFi Module:

Other Tools and Components:

Top Arduino Sensors:

Super Starter kit for Beginners

Digital Oscilloscopes

Variable Supply

Digital Multimeter

Soldering iron kits

PCB small portable drill machines

*Please Note: These are affiliate links. I may make a commission if you buy the components through these links. I would appreciate your support in this way!

ESP8266 (NodeMCU):

ESP8266 is a highly integrated chip designed for the needs of a new connected world. It offers a complete and self-contained Wi-Fi networking solution, allowing it to either host the application or to offload all Wi-Fi networking functions from another application processor.
ESP8266 has powerful on-board processing and storage capabilities that allow it to be integrated with the sensors and other application-specific devices through its GPIOs with minimal development up-front and minimal loading during runtime. Its high degree of on-chip integration allows for minimal external circuitry, and the entire solution, including front-end module, is designed to occupy minimal PCB area.

ESP8266 with Telegram


Serial/UART baud rate: 115200 bps
Input power: 3.3V
I/O voltage tolerance: 3.6V Max
Flash Memory Size: 1MB (8Mbit)
WiFi security modes: WPA, WPA2

DHT 11 Sensor:

  • DHT11 digital temperature and humidity sensor is a digital signal output with a calibrated temperature and humidity combined sensor.
  • It uses a dedicated digital modules and acquisition of temperature and humidity sensor technology to ensure that products with high reliability and excellent long term stability.
  • Sensor consists of a resistive element and a sense of wet NTC temperature measurement devices, and with a high-performance 8-bit microcontroller connected.
  • The product has excellent quality, fast response, anti-interference ability, high cost and other advantages.
  • The single-wire wiring scheme makes it easy to be integrated to other applications and the simple communication protocol greatly reduces the programming effort required.

ESP8266 with Telegram

Nodemcu ESP8266 with DHT11 Circuit Diagram:

Connect pin number1 of the DHT11 sensor with the 3.3V pin of the Nodemcu ESP8266. Connect pin number2 which is the data pin with the D1 pin of the Nodemcu ESP8266. Pin number3 is not connected. Finally, connect pin number4 of the DHT11 sensor with the GND pin of the Nodemcu ESP8266 WiFi Module. These are the minimum connections which you can start with, you can use your laptop or computer to power up the Nodemcu ESP8266. But if you want to practically implement this then you will need to add an external power supply; I have a very detailed video on this, I will provide a link in the description. Now, let’s start the interfacing.

  • Connect the middle pin which is signal pin of the DHT11 with the D1 of the ESP8266.
  • Connect the ground of the DHT11 with the ground of the ESP8266.
  • Connect the VCC of the DHT11 with the 3V of the ESP8266.

ESP8266 with Telegram

ESP8266 with Telegram

Connect the data pin with the D1 pin.

Connect the VCC pin with 3.3V pin.

Finally, connect the GND pin of the DHT11 Sensor with the GND pin of the Nodemcu ESP8266. Our interfacing is completed.

Creating Telegram Bot:

First of all download the telegram app from the play store which is available free of cost. Then open the telegram app and in the search write botfather with the help of which we will design the app.

ESP8266 with Telegram

Then we will create the new Bot for our application for which we will write /newbot

ESP8266 with Telegram

When we will write this command we will receive the message that choose the name for your bot

ESP8266 with Telegram

Next, we will choose the username, we can select any name but it must end in bot. Our Bot is created and we can use this token to access the HTTP API, we will use this in the Nodemcu ESP8266 programming.

ESP8266 with Telegram

Nodemcu ESP8266 Board Manager Installation:

If this is your first time using the Nodemcu ESP8266 WiFi module, then first of all, you will need to install the Nodemcu board, as you can see the Nodemcu board is not installed.

ESP8266 with Telegram

To install the Nodemcu board click on the file menu and then click on the preferences.

ESP8266 with Telegram

Then in the preference paste the following link

As we are going to install both ESP32 and E8266 board setup so will paste both links separated by comma and click on ok. If you want to install the esp8266 only then copy the second link.

ESP8266 with Telegram

After that we will again open the board manager for which we will click on the tools and then select the board manager.

ESP8266 with Telegram

Click on the board manager. Type ESP8266 in the search box, select the latest version and then click on the install button. This may take several minutes depending on the internet speed. Click on the Close button when the installation is completed.

Then we will select the NodeMCU

ESP8266 with Telegram

After installing the NodeMCU board we will install the library for the telegram app for which we will go to the sketch, then click on the include library and then click on the manage library.

ESP8266 with Telegram

In the library manager we will write the telegram and install the UniversalTelegramBot library. I have already installed this library.

ESP8266 with Telegram

Telegram Nodemcu ESP8266 Programming:

Telegram Nodemcu ESP8266 Code Explanation:

First of all we will add the libraries for the Nodemcu, Telegram, and DHT11 sensor.

Next, I defined a pin to which the Dht11 sensor is connected, in my case D1.

Then we will write the WiFi name and password.

Here we will paste the command bot token which we have copied during the telegram bot creation.

Now with WifiClientSecure create Wifi client

Now create a bot from the client and bot token

Checks for new messages every 1 second.

This function will handle the message which will be received from the telegram application

Now if the message received from the telegram temperature then it will send temperature to the telegram application.

This command will store the current value of the temperature

Then we have declare temp of string variable type in which we will save the temperature and its value and send it to the telegram.

If we receive humidity message from the telegram application then it will read the humidity and send it to the telegram.

This command will read the humidity and store it in the variable then we have declare string variable which will store the text humidity and its value in percentage and send it to the telegram application.

Now if we receive the message start from the user then it will display temperature and humidity.

In the setup function we will start the serial communication of the DHT sensor and connect the Wifi with the router.

Here we will get the temperature and humidity values from the sensor.

After uploading code to the NodeMCU ESP8266 we will open the telegram application and open the temp monitoring chat. When we will write /start in it we will get the message /temperature and /humidity. If we click or write /temperature then we will get the temperature and if we click or wrtie the /humidity then we will get the percentage of humidity.

ESP8266 with Telegram

Watch Tutorial:


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About the Author: Engr Fahad

My name is Shahzada Fahad and I am an Electrical Engineer. I have been doing Job in UAE as a site engineer in an Electrical Construction Company. Currently, I am running my own YouTube channel "Electronic Clinic", and managing this Website. My Hobbies are * Watching Movies * Music * Martial Arts * Photography * Travelling * Make Sketches and so on...

1 Comment

  1. How do I manage to get from the “Token” message to the next step to select the ESP board ? How to activate this window ?

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