Removing elements from a JavaScript array means taking out certain items from the array. This is a basic and important task in programming because it helps keep the array accurate and makes data handling easier. In this article, we will discuss few methods to remove elements from a JavaScript Array.

Methods to Remove Elements from JavaScript Array

There are different methods to remove elements from a JavaScript array which are discussed below: 

Note: There are other methods that are created by JavaScript inbuilt methods.

Method 1: Remove Last Element form Array using pop() Method

This method is used to remove the last element of the array and returns the removed element. This function decreases the length of the array by 1 every time the element is removed. 

Example 1: The below code is the basic implementation of the pop() method to remove elements from an array.

// JavaScript code to illustrate pop() function 
// to remove array elements

let arr = ["shift", "splice", "filter", "pop"];

// Popping the last element from the array 
let popped = arr.pop();
console.log("Removed element: " + popped);
console.log("Remaining elements: " + arr);
console.log("Array length: " + arr.length);

Removed element: pop
Remaining elements: shift,splice,filter
Array length: 3

Example 2: The below code removes the elements from array using pop() method until the length of the array turns to 0.

// Declare and initialize an array
let array = ["pop", "splice", "filter", "shift"]

console.log("Original array: " + array)

// Loop run while array length not zero
while (array.length) {

    // Remove elements from array
    array.pop();
}
console.log("Array Length: " + array.length)

Original array: pop,splice,filter,shift
Array Length: 0

// JavaScript code to illustrate shift() method
// to remove elements from array
let arr = ["shift", "splice", "filter", "pop"];

// Removing the first element from array 
let shifted = arr.shift();
console.log("Removed element: " + shifted);
console.log("Remaining elements: " + arr);

Removed element: shift
Remaining elements: splice,filter,pop

// JavaScript code to illustrate splice() function 

let arr = ["shift", "splice", "filter", "pop"];

// Removing the specified element from the array 
let spliced = arr.splice(1, 1);
console.log("Removed element: " + spliced);
console.log("Remaining elements: " + arr);

Removed element: splice
Remaining elements: shift,filter,pop

// JavaScript code to illustrate splice() function 
let arr = ["shift", "splice", "filter", "pop"];

// Removing the specified element by value from the array 
for (let i = 0; i < arr.length; i++) {
    if (arr[i] === "splice") {
        let spliced = arr.splice(i, 1);
        console.log("Removed element: " + spliced);
        console.log("Remaining elements: " + arr);
    }
}

Removed element: splice
Remaining elements: shift,filter,pop

Example 3: Using the splice method to remove each element from a JavaScript array. 

// Declare and initialize array
let array = ["pop", "splice", "filter", "shift"]

console.log("Original array: " + array)

// Making the length of array to 0 by using splice method
array.splice(0, array.length);
console.log("Empty array: " + array)

Original array: pop,splice,filter,shift
Empty array: 

Method 4: Remove Element from Array with Certain Condition using filter() Method

Filter method is used to create a new array from a given array consisting of only those elements from the given array which satisfy a condition set by the argument function. To remove elements by filter() method you can specify the elements in different ways. 

Example: The below example uses the value of the filter method to remove elements from a JavaScript array. 

// JavaScript to illustrate filter() method
function isPositive(value) {
    return value > 0;
}

function func() {
    let filtered = [101, 98, 12, -1, 848].filter(isPositive);
    console.log("Positive elements in array: " + filtered);
}
func(); 

Positive elements in array: 101,98,12,848

Method 5: Remove Array Elements with Index using Delete Operator

The delete operator returns a boolean value, true, if the element or property is removed from the array or object and false, if a function or variable is passed to remove.

Example: The below code implements the delete operator to remove elements from an array.

// Declare and initialize an array
let array = ["lodash", "remove", "delete", "reset"]

// Delete element at index 2
let deleted = delete array[2];

console.log("Removed: " + deleted);
console.log("Remaining elements: " + array);

Removed: true
Remaining elements: lodash,remove,,reset

Method 6: Remove Array Elements using Clear and Reset Approach

Removing elements from an array using the manual clear and reset approach either by resetting the length of the array as 0 using the length property or by assigning the array to an empty array([]).

Example: This example explains how you can implement the clear and reset approach in JavaScript.

// Declare and initialize an array
let array1 = ["lodash", "remove", "delete", "reset"];
let array2 = [1, 2, 3, 4, 5];

console.log("Array1 before elements removal: ", array1);
console.log("Array2 before elements removal: ", array2);

// Delete each element of array
array1 = [];
array2.length = 0;
console.log("Array1 after elements removal: ", array1);
console.log("Array2 after elements removal: ", array2);

Array1 before elements removal:  [ 'lodash', 'remove', 'delete', 'reset' ]
Array2 before elements removal:  [ 1, 2, 3, 4, 5 ]
Array1 after elements removal:  []
Array2 after elements removal:  []

Method 7: Remove Element from Array using for() loop and new array

Here a simple for loop will be run over the array and pushes all elements in the new array except the element that has to be removed.

Example: The below example uses the for loop and a new array to remove elements from an array.

let removeElement = (array, n) => {
    let newArray = [];

    for (let i = 0; i < array.length; i++) {
        if (array[i] !== n) {
            newArray.push(array[i]);
        }
    }
    return newArray;
};

let passed_in_array = [1, 2, 3, 4, 5];
let element_to_be_removed = 2;
let result = removeElement(passed_in_array, element_to_be_removed);

console.log("Remaining elements: " + result);

Remaining elements: 1,3,4,5

Method 8: Remove Array Element using lodash _.remove Method

Use the lodash library to remove elements from a JavaScript array. To use lodash library you need to install it locally on your system.

Example: This code implements the _.remove() method of lodash to remove element from an array.

// Import Lodash library
const _ = require('lodash');

// Declare and initialize an array
let array = [101, 98, 12, -1, 848];

// using _.remove to remove odd number
let evens= _.remove(array, function(n) {
    return n % 2 == 0;
});
    
console.log("Remaining odd elements: " + array);
console.log("Removed even elements: " + evens);  

Output: 

Removed odd elements: 101, -1
Remaining even elements: 98, 12, 848

Method 9: Using JavaScript Array.prototype.reduce Method

Another approach to remove elements from an array in JavaScript is by using the reduce method. This method allows for iterating over the array and accumulating a new array that excludes the elements that need to be removed based on a condition.

Example: In this example, we will use the reduce method to create a new array that excludes certain elements based on a specified condition.

function removeElements(array, condition) {
    return array.reduce((acc, curr) => {
        if (!condition(curr)) {
            acc.push(curr);
        }
        return acc;
    }, []);
}
const originalArray = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
const isOdd = (num) => num % 2 !== 0;

const newArray = removeElements(originalArray, isOdd);

console.log('Original Array:', originalArray); 

console.log('New Array (Even Numbers):', newArray); 

Original Array: [
  1, 2, 3, 4,  5,
  6, 7, 8, 9, 10
]
New Array (Even Numbers): [ 2, 4, 6, 8, 10 ]

Method 10: Remove Element from Array using forEach(), indexOf(), and splice()

This method uses forEach to iterate over the array and indexOf to find the index of the element that needs to be removed. The splice method is then used to remove the element at that index.

Example: The below example demonstrates how to remove a specific element from an array using forEach, indexOf, and splice.

// Function to remove specific element from array
function removeElement(array, elementToRemove) {
    array.forEach((item, index) => {
        if (item === elementToRemove) {
            array.splice(index, 1);
        }
    });
    return array;
}

// Declare and initialize an array
let array = ["shift", "splice", "filter", "pop"];

console.log("Original array: " + array);

// Remove specific element from array
removeElement(array, "filter");

console.log("Array after removing 'filter': " + array);

Original array: shift,splice,filter,pop
Array after removing 'filter': shift,splice,pop