Get MAC Address of ESP8266 NodeMCU

A MAC (Media Access Control) address is a unique number that assigned to a network adapter by the manufacturer to uniquely identify it. A MAC address is commonly represented as a string of six hexadecimal numbers separated by colons, such as A4:CF:12:AF:C2:36.

This tutorial shows how to get the MAC address of ESP8266 NodeMCU development board.

Components

Code

In order to get the MAC address, we can use the macAddress member function of WiFi global variable. We will get the MAC address as a string if no arguments provided to the function.

#include <ESP8266WiFi.h>

void setup()
{
    Serial.begin(9600);

    String mac = WiFi.macAddress();
    Serial.println(mac);
}

void loop() {}

Also it is possible to get the MAC address stored in an unsigned char array.

#include <ESP8266WiFi.h>

void setup()
{
    Serial.begin(9600);

    unsigned char mac[6];
    WiFi.macAddress(mac);

    Serial.printf(
        "%02X:%02X:%02X:%02X:%02X:%02X",
        mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]
    );
}

void loop() {}