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Compare JSON objects ignoring the order of the properties in JavaScript

To compare two JSON objects we cannot use equality operators === (in case of JavaScript), == (in case of Java).

In JavaScript we primarily compare two JSON objects by converting them to their string versions using JSON.stringify. It  seems to be the most obvious and easiest choice for comparison as no external dependency is required. But there’s a problem, what if the JSON objects have same properties but in different order. The equality check would fail in this case. This is why we don’t recommend to use JSON.stringify while comparing JSON objects.

We have a few options to compare two JSON objects and ensure equality.

Lodash’s .isEqual() is our favorite pick.

var _ = require('lodash');
_.isEqual({a:1, b:2}, {b:2, a:1});
//true
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fast-equals is another option which provides blazing fast equality comparisons.

import { deepEqual } from 'fast-equals';
console.log(deepEqual({a:1, b:2}, {b:2, a:1})); // true
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deep-equal which is Node’s assert.deepEqual() algorithm as a standalone module. This module is around 46 times faster than wrapping assert.deepEqual() in a try/catch.

var equal = require('deep-equal');
console.log(equal({a:1, b:2}, {b:2, a:1})); // true

deep-equal performs well than JSON.stringify() as tested by Matt Zeunert.

deepEqual is 42% slower than a comparison with JSON.stringify

Another way written by Subash Chandran based on deep-equal-in-any-order.

See also  Split an array into half in JavaScript

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