Fastest way to compare 2 objects in js

javascript compare two objects and get differences
how to compare two json objects in javascript
how to compare two objects in javascript
lodash compare objects
compare two json objects and get difference javascript
javascript compare object key values
javascript compare two arrays of objects
javascript compare two empty objects

Which is the fastest way to compare 2 objects in javascript?

For example I have these 2 objects:

a = [{'name': 'john', 'age': 22}, {'name': 'mike', 'age': 23}, {'name': 'anne', 'age': 12}, {'name': 'dan', 'age': 29}, {'name': 'jane', 'age': 34}]
b = [{'name': 'john', 'age': 22}, {'name': 'anne', 'age': 12}]

Normally, I would do this:

for (var i = 0; i < a.length; i++) {
    for (var j = 0; j < b.length; j++) {
        console.log(a[i]) // => [{'name': 'john', 'age': 22}, {'name': 'anne', 'age': 12}]

This is taking too long, is it there another way faster? Thank you for your time!


You can have a look at the fast-deep-equal package. Here is a performance benchmark from their for your reference.

fast-deep-equal x 226,960 ops/sec ±1.55% (86 runs sampled)
nano-equal x 218,210 ops/sec ±0.79% (89 runs sampled)
shallow-equal-fuzzy x 206,762 ops/sec ±0.84% (88 runs sampled)
underscore.isEqual x 128,668 ops/sec ±0.75% (91 runs sampled)
lodash.isEqual x 44,895 ops/sec ±0.67% (85 runs sampled)
deep-equal x 51,616 ops/sec ±0.96% (90 runs sampled)
deep-eql x 28,218 ops/sec ±0.42% (85 runs sampled)
assert.deepStrictEqual x 1,777 ops/sec ±1.05% (86 runs sampled)
ramda.equals x 13,466 ops/sec ±0.82% (86 runs sampled)
The fastest is fast-deep-equal

How to compare two objects in JavaScript?, Comparing objects is easy, use === or This function returns true if they have the same reference and false if they do not. Objects are not like arrays or strings. So simply comparing by using "===" or "==" is not possible. Here to compare we have to first stringify the object and then using equality operators it is possible to compare the objects. In the following example, objects were stringified () at first and then compared with each other.

let a={a:20,b:10};
let b={b:10,a:20};

            Object.entries(b).sort().toString()) //true

Node.js assert.deepEqual() Method, That comparison by reference basically checks to see if the objects given refer to the same location in memory. Here is an example of how that works. One quick way to compare if 2 objects have the same key value, is using JSON.stringify. Another way is using Lodash isEqualfunction 👏. constk1 ={fruit:'🥝'};constk2 ={fruit:'🥝'};// Using JavaScriptJSON.stringify(k1)===JSON.stringify(k2);// true// Using Lodash_.isEqual(k1,k2);// true. Deep Nested Comparison.

a = [{'name': 'john', 'age': 22}, {'name': 'mike', 'age': 23}, {'name': 'anne', 'age': 12}, {'name': 'dan', 'age': 29}, {'name': 'jane', 'age': 34}]
b = [{'name': 'john', 'age': 22}, {'name': 'anne', 'age': 12}]

var areTheyEqual = JSON.stringify(a) === JSON.stringify(b) ;

console.log('Are they equal: ' + areTheyEqual)

Comparing Java objects with equals() and hashcode(), So what is the best way to compare objects in JavaScript? true; // Try a quick compare by seeing if the length of properties are the same let firstProps = Object. JavaScript provides 3 ways to compare values: The strict equality operator === The loose equality operator == function; When comparing objects using any of the above, the comparison evaluates to true only if the compared values reference the same object instance. This is the referential equality.

Difference Between =, ==, and === in JavaScript [Examples], Objects are not like arrays or strings. So simply comparing by using === or == is not possible. Here to compare we have to first stringify the  Another way to compare two objects is to convert them to JSON and check if the resulting strings are equal: functionjsonEqual(a,b){returnJSON.stringify(a)===JSON.stringify(b);}jsonEqual(user1,user2)// true in all three cases above Like deepEqualthis method cares about the contents of the object, rather than referential equality.

Fastest way to compare 2 objects in js, The fastest deep equality check with Date, RegExp and ES6 Map, Set and typed ES5 compatible; works in node.js (8+) and browsers (IE9+); checks equality of var equal = require('fast-deep-equal/es6'); console.log(equal(Int16Array([1, 2]), needed when comparing the elements - borrowed from react-fast-compare):. By the way, I do not suggest JSON.stringify() to compare two objects. Once you do this you are comparing strings not Objects! Thanks for reading and happy coding!

Comparing Objects in JavaScript, //How To Compare Object Values. var a = { blah: 1 };. var b = { blah: 1 };. var c = a;. var d = { blah: 2 };. = function (obj1, obj2) {. Now we are writing the compare function it helps us to compare above two arrays. Let’s start. Step 1: We need to declare the function with two parameters. function compare(arr1,arr2){} Step 2: We need to Initialize an empty array. function compare(arr1,arr2){const finalarray =[];}