Detect magnets with your Arduino! This Hall Effect sensor module senses magnetic fields and gives a simple digital ON/OFF output — no complex wiring, no analog calibration. Just power it, bring a magnet close, and watch the output change. It is the easiest way to add speed measurement, position sensing and RPM counting to any project. Works with Arduino, ESP32 and other 3.3V or 5V boards — explore our Sensors collection.

Key Features

• Digital magnetic field detection (Hall Effect, A3144 IC or compatible)
• Clean digital output — HIGH normally, LOW when a magnet is detected
• Simple 3-pin interface: GND, VCC, Signal
• Wide operating voltage: 3.3V – 5V (Arduino and ESP32 compatible)
• Onboard signal indicator LED
• Compact module, breadboard and PCB friendly

How to Connect (Usage)

Wire the module to your Arduino as follows:

Arduino Example Code

const int hallPin = 2;   // signal pin
void setup() {
  pinMode(hallPin, INPUT);
  Serial.begin(9600);
}
void loop() {
  int state = digitalRead(hallPin);
  if (state == LOW) {
    Serial.println("Magnet detected!");
  }
  delay(200);
}

Upload this to any Arduino board — open the Serial Monitor and bring a magnet near the sensor to see it trigger.

Applications

• Speed measurement (wheels, shafts, fans)
• RPM counter / tachometer projects
• Position and proximity detection
• Limit switch for CNC and 3D printers
• Robotics Projects — see our Robotics parts
• Door/window open-close sensing
• DIY Electronics — more modules

Frequently Asked Questions

Q: What does a Hall Effect sensor actually do?
A: It detects magnetic fields. When a magnet comes close to the sensor IC, the module’s digital output switches state — your microcontroller simply reads HIGH or LOW.

Q: How do I connect it to an Arduino?
A: Three wires only: VCC to 5V, GND to GND, and the Signal pin to any digital input pin. The example code above gets you running in minutes.

Q: Does it work on 3.3V boards like the ESP32?
A: Yes — the module accepts 3.3V to 5V, so it works directly with both Arduino (5V) and ESP32/ESP8266 (3.3V) boards.

Q: Digital or analog — which one is this?
A: This is the digital version: it outputs a clean ON/OFF signal, which is the simplest choice for counting, speed sensing and detection tasks.

Q: What can students build with it?
A: A digital tachometer/RPM meter, a bicycle speedometer, a magnetic door alarm, motor speed control feedback, and robot wheel encoders — all great final-year and school science projects.

Q: Where can I buy sensors in Pakistan?
A: Right here — QKZee Technologies stocks Hall Effect and other sensor modules at our Hall Road, Lahore shop with Cash on Delivery across Pakistan.