How to Make Metal Detector with Arduino and Inductive Sensor


Welcome to the world of metal detection with Arduino! In this guide, we’ll explore How to Make Metal Detector with Arduino and Inductive Sensor. An inductive sensor is a type of proximity sensor that detects the presence of metallic objects without physical contact. By measuring changes in inductance, the sensor can identify the presence and location of metal objects. Let’s delve into the details of the inductive sensor and learn how to integrate it with Arduino to build a metal detector.

Hardware Required

You will require the following Hardware Components for How to Interface the Inductive Sensor with Arduino.

Components#Buy From Amazon
Arduino UNO1Buy Link
Inductive Sensor1Buy Now
9v DC Adapter (Optional)1Buy Link
Jumper Wires3Buy Link
Breadboard1Buy Link

What is an Inductive sensor?

An inductive sensor is a proximity sensor designed to detect metal objects. It can be easily connected to a controller or processor such as Arduino.

Internally, these sensors consist of a magnetic field generator and an inductor coil that detects the field generated by the sensor itself.

The presence of a metallic object alters the induced field. Since metals have lower magnetic resistance (reluctance), the magnetic field extends further, increasing the current induced in the sensor coil.

This modified field is detected by the sensor electronics, which activate their output when metal is detected. As these sensors have two states, they are sometimes referred to as inductive proximity switches.


Inductive sensors come in two types: normally open (NO) and normally closed (NC). NO sensors output LOW when no object is detected, while NC sensors output HIGH in the same scenario.

Detection range depends on the metal, generally not exceeding millimeters. Ferritic metals offer wider ranges, while non-ferritic metals reduce it by 60%.

Inductive sensors operate without physical contact and can detect metal objects even when covered by other materials like plastic. They excel in industrial environments with dirt and dust.

Used in industrial automation, elevators, vehicle detection, and construction for various tasks like part detection and pipe/nail detection.

In Arduino projects, they’re useful for detecting objects, obstacles, door closures, and objects on a table.



Pin Configuration

Pin NameDescription
VINModule power supply – 6-36 V (Brown)
GNDGround (Blue)
OUTDigital output (Black)


  1. Sensing Range:
    • Determines the distance at which the sensor can detect metallic objects.
  2. Operating Voltage:
    • Specifies the voltage range required for the sensor to function properly.
  3. Output Type:
    • Indicates the type of output signal generated by the sensor (e.g., digital, analog).
  4. Response Time:
    • Defines the time taken by the sensor to detect a metallic object and generate an output signal.
  5. Operating Temperature:
    • Specifies the temperature range within which the sensor can operate reliably.


  1. Non-Contact Detection:
    • Detects metallic objects without physical contact, reducing wear and tear.
  2. High Sensitivity:
    • Offers high sensitivity to metallic objects, ensuring accurate detection.
  3. Compact Design:
    • Compact and lightweight design for easy integration into electronic projects.
  4. Adjustable Sensitivity:
    • Some inductive sensors feature adjustable sensitivity settings to customize detection capabilities.
  5. Reliability:
    • Provides reliable and consistent performance in detecting metallic objects.

Circuit Diagram

The following circuit shows you the connection of the How to Make Metal Detector with Arduino and Inductive Sensor. Please make the connection carefully


Circuit Connections

ArduinoInductive Sensor
+5VVIN (Brown wire)
GNDGND (Blue wire)
D9OUT (Black wire)

Installing Arduino IDE Software

First, you will require to Download the updated version of Arduino IDE Software and Install it on your PC or laptop. if you Learn How to install the Arduino step-by-step guide then click on how to install Arduino Button given Blow


//For more Projects:

const int sensorPin = 9;

void setup()

void loop()
   bool state = digitalRead(sensorPin);

   //send message to serial port based on the value read
   if (state == HIGH)
      //here the actions would be executed


  1. Metal Detection Systems: Use inductive sensors to build metal detection systems for security checkpoints, industrial applications, and archaeological surveys.
  2. Conveyor Belt Monitoring: Incorporate inductive sensors into conveyor belt systems to detect metal contaminants and prevent equipment damage.
  3. Material Handling: Integrate inductive sensors into material handling equipment to detect metal parts or components during sorting and assembly processes.
  4. Automated Machinery: Utilize inductive sensors in automated machinery for detecting metal objects in robotic arms, pick-and-place systems, and sorting mechanisms.
  5. Vehicle Detection: Install inductive sensors in roadways or parking lots for vehicle detection, traffic control, and toll collection applications.


Inductive sensors offer a reliable and efficient solution for detecting metallic objects in various applications. By leveraging the capabilities of Arduino, we can easily integrate an inductive sensor into a metal detection system and create customized solutions for specific needs. Whether you’re building a security scanner, monitoring conveyor belts, or automating machinery, the combination of Arduino and an inductive sensor provides endless possibilities for metal detection projects. Let’s explore the potential of inductive sensors and unleash our creativity in building innovative metal detection solutions!

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