ESP-01S DHT11 Temperature Humidity Sensor module

ESP-01S DHT11 Sensor Module

WiFi + Temperature + Humidity IoT Ready

What is this module?

The ESP-01S DHT11 module is a compact IoT sensor board that combines:

• ESP-01S (ESP8266 WiFi module)

• DHT11 temperature & humidity sensor

It can measure environmental data and send it over WiFi without needing an external Arduino.

Working Principle

• DHT11 sensor measures:

  • Temperature

  • Humidity

   

• ESP8266 (ESP-01S):

  • Reads data from DHT11

  • Processes it

  • Sends data via WiFi (HTTP/MQTT/etc.)

   

Acts as a standalone IoT device

Main Components

1. E/p

Handles communication and processing

2. DHT11 Sensor

• Measures temperature and humidity

• Digital output

Pin Configuration (ESP-01S Side)

• VCC 3.3V

• GND Ground

• TX Serial transmit

• RX Serial receive

• GPIO0 / GPIO2 General purpose pins

• EN (CH_PD) Enable pin

DHT11 is internally connected (usually to GPIO2)

Technical Specifications

ESP-01S (ESP8266)

• Operating Voltage: 3.3V (strict)

• WiFi Standard: 802.11 b/g/n

• Flash Memory: 1MB

• GPIO Pins: 2 usable (GPIO0, GPIO2)

• Humidity Range: 20% to 90% RH

• Temperature Accuracy: 2C

• Humidity Accuracy: 5% RH

• Sampling Rate: 1 reading per second

ge:

0C to 50C

Output & Communication

• Sensor data is:

  • Read digitally from DHT11

  • Transmitted via WiFi

   

Supports:

• HTTP (web server)

• MQTT (IoT platforms)

• Serial communication (for debugging)

Key Features

• Built-in WiFi capability

• Compact and low-cost IoT solution

• No external microcontroller required

• Easy integration with cloud platforms

• Real-time environmental monitoring

Applications

• Ioing

• Remote temperature logging

• Server room monitoring

• Agriculture/environment monitoring

Advantages

• Combines sensor + WiFi in one module

• Reduces wiring and hardware complexity

• Suitable for wireless projects

• Low cost and widely available

Limitations

• Requires stable 3.3V power (not 5V tolerant)

• Limited GPIO pins

• DHT11 has lower accuracy than advanced sensors

• Needs programming via USB-to-Serial adapter

Important Notes

• Always use a 3.3V regulated power supply

• Do not connect directly to 5V (can damage ESP8266)

• Use proper firmware (Arduino IDE or AT firmware)

• Add capacitor (e.g., 100F) for stable power

1S DHT11 Sensor Module is an all-in-one IoT solution that:

Measures temperature and humidity Sends data over WiFi Works without Arduino

Ideal for:

• Beginners learning IoT

• Wireless monitoring systems

• Smart environme