Why Do Two Empty JavaScript Objects Not Compare as Equal?

Why are Two Identical Objects Not Identical to Each Other?

In JavaScript, the equality operator (==) and the strict equality operator (===) are used to compare values. However, when comparing objects, these operators behave differently than you might expect.

Consider the following code:

var a = {};
var b = {};

console.log(a == b); // returns false
console.log(a === b); // returns false

This code logs false for both expressions, even though a and b are both empty objects. Why is this?

The key difference between regular (==) and strict (===) equality is that the strict equality operator disables type conversion. Since a and b are both objects, the type of equality operator doesn't matter in this case.

Regardless of the equality operator used, object comparisons only evaluate to true if you compare the same exact object. In other words, given var a = {}, b = a, c = {};, a == a, a == b, but a != c.

Two different objects (even if they have zero or the same exact properties) will never compare equally. To compare the equality of two objects' properties, you can use the Object.is() method or the approach outlined in the provided answer.

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