ESP32 WiFi Library – WiFi.subnetMask

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Description

The subnetMask method retrieves the subnet mask of the currently connected Wi-Fi network. A subnet mask defines the range of IP addresses that belong to the same network and is used to determine which part of the IP address represents the network and which part represents the host.

Syntax and Usage

This method returns the subnet mask of the network to which the ESP32 is connected.

WiFi.subnetMask()

Argument(s)

This method does not accept any arguments.

Return Value

The subnetMask method returns an IPAddress object that contains the subnet mask of the connected Wi-Fi network. If the ESP32 is not connected to a Wi-Fi network, this method will return 0.0.0.0.

Example Codes

Retrieve and print the subnet mask

This code demonstrates how to use the ESP32 WiFi Library’s subnetMask() method to retrieve the subnet mask of the currently connected WiFi network. The subnet mask defines the range of IP addresses that belong to the same network and helps determine which part of an IP address represents the network and which part represents the host. After connecting to the network, the code fetches and prints the subnet mask using WiFi.subnetMask().

To use this code, replace “your_SSID” and “your_PASSWORD” with your WiFi network’s SSID and password. Upload the code to your ESP32 board and open the Serial Monitor at 115200 baud. The code will connect to the WiFi network and display the subnet mask. Ensure the ESP32 is within range of the WiFi signal for a successful connection.

/*
 * Author: Avant Maker
 * Date: February 8, 2025
 * Version: 1.0
 * Description: This code demonstrates how to connect an ESP32 to a 
 * WiFi network and retrieve the subnet mask of the connected network 
 * using the ESP32 WiFi library's WiFi.subnetMask. 
 *
 * License: MIT 
 * 
 * Code Source: This example code is sourced from the Comprehensive Guide
 * to the ESP32 Arduino Core Library, accessible on AvantMaker.com. 
 * For additional code examples and in-depth documentation related to 
 * the ESP32 Arduino Core Library, please visit:
 *
 * https://avantmaker.com/references/esp32-arduino-core-index/
 *
 * AvantMaker.com, your premier destination for all things DIY, AI, IoT, 
 * Smart Home, and STEM projects. We are dedicated to empowering makers,
 * learners, and enthusiasts with the resources they need to bring their 
 * innovative ideas to life.
 */

#include <WiFi.h>

const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";

void setup() {
    Serial.begin(115200);
    WiFi.begin(ssid, password);

    Serial.println("Connecting to WiFi...");
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }
    Serial.println("\nConnected to WiFi!");

    // Retrieve and print the subnet mask
    IPAddress subnet = WiFi.subnetMask();
    Serial.print("Subnet Mask: ");
    Serial.println(subnet);
}

void loop() {
    // Your code here
}