How to Check if an Object is Empty in JavaScript

Objects in JavaScript are a collection of key-value pairs.

Sometimes it can be useful to know if an object is empty or not. For example, you might want to check if an object is empty before you try to access a property on it.

In this post, we'll learn how to check if an object is empty in JavaScript.

How to check if an object is empty in JavaScript

There are a few ways to check if an object is empty in JavaScript.

First, let's start with an example empty object:

	const object = {};

The best way to check an object is empty is to use the Object.entries() method.

This method returns an array of a given object's own enumerable key-value pairs.

If the object is empty, the array will be empty.

	const object = {};

if (Object.entries(object).length === 0) {
    console.log("Object is empty");
} else {
    console.log("Object is not empty");
}

	Object is empty

Alternatively, we can turn this into a method:

	const object = {};

const isEmpty = (obj) => Object.entries(obj).length === 0;

if (isEmpty(object)) {
    console.log("Object is empty");
} else {
    console.log("Object is not empty");
}

	Object is empty

Just make sure the variable that you are using is an object.

If you want to check, you can compare the constructor:

	const object = {};

const isObject = (obj) => obj.constructor === Object;

if (isObject(object)) {
    console.log("Object is an object");
} else {
    console.log("Object is not an object");
}