When working with JavaScript it is common to compare objects for equality. we will explore various approaches to compare objects for equality in JavaScript.

These are the following approaches:

Using JSON.stringify

In this approach, we convert the objects to JSON strings using JSON.stringify and compare the resultant strings for equality.

Example: The below example uses the JSON.stringify method to Compare Objects for Equality.

const isEqual = (obj1, obj2) => JSON.stringify(obj1) === JSON.stringify(obj2);
const obj1 = {
    org: 'GeeksForGeek',
    founder: "Sandeep Jain"
};
const obj2 = {
    org: 'GeeksForGeek',
    founder: "Sandeep Jain"
};

console.log(isEqual(obj1, obj2));

true

Using Lodash’s isEqual() Method

In this approach, we are using Lodash’s isEqual() Method. The isEqual() method is used to deeply compare two values to determine if they are equivalent.

Example: Below example uses Lodash’s isEqual() method to Compare Objects for Equality.

const isEqual = require('lodash/isEqual');

const obj1 = {
    org: 'GeeksForGeek',
    founder: "Sandeep Jain"
};
const obj2 = {
    org: 'GeeksForGeek',
    founder: "Sandeep Mishra"
};

console.log(isEqual(obj1, obj2));

Output:

false

Using Object.keys() and Array.every()

In this approach, we use Object.keys() to get all the keys of the objects and then use the Array.every() method to check if all the keys and their corresponding values are equal in both objects.

Example: The below example uses Object.keys() and Array.every() to compare objects for equality.

const isEqual = (obj1, obj2) => {
    const keys1 = Object.keys(obj1);
    const keys2 = Object.keys(obj2);

    if (keys1.length !== keys2.length) {
        return false;
    }

    return keys1.every(key =>
        obj2.hasOwnProperty(key) && obj1[key] === obj2[key]);
};

const obj1 = { org: 'GeeksForGeek', founder: "Sandeep Jain" };
const obj2 = { org: 'GeeksForGeek', founder: "Sandeep Jain" };

console.log(isEqual(obj1, obj2));

Output:

true

Using Object.entries() and Array.every()

In this approach, we use Object.entries() to get all key-value pairs of the objects and then use Array.every() to check if all key-value pairs are equal in both objects.

Example: In this example The isEqual function checks if two objects (obj1 and obj2) have the same properties and values. It compares their entries and ensures both objects have identical keys and corresponding values for each key.

const isEqual = (obj1, obj2) => {
    const entries1 = Object.entries(obj1);
    const entries2 = Object.entries(obj2);

    if (entries1.length !== entries2.length) {
        return false;
    }

    return entries1.every(([key, value]) =>
        obj2.hasOwnProperty(key) && obj2[key] === value);
};

const obj1 = { org: 'GeeksForGeek', founder: "Sandeep Jain" };
const obj2 = { org: 'GeeksForGeek', founder: "Sandeep Jain" };

console.log(isEqual(obj1, obj2));

true