# JavaScript, how to get the class name of an object

> Learn how to get the class name of an object in JavaScript by reading its constructor name property, plus how to compare the constructor to a class directly.

Author: [Flavio Copes](https://flaviocopes.com/about/) | Published: 2022-04-29 | Topics: [JavaScript](https://flaviocopes.com/tags/js/) | Canonical: https://flaviocopes.com/javascript-get-object-class-name/

Suppose you have an object that's generated from a class, and you want to get its class name.

For example, let's use this code as reference:

```js
class Dog {
  
}

const roger = new Dog()
```

Of course now we know that `roger` is an object that's created from the class `Dog`.

But how do you get the class name of the object, in case you don't know it?

You can lookup the object's constructor, then reference its `name` property.

In this example:

```js
class Dog {
  
}

const roger = new Dog()

console.log(roger.constructor.name) // 'Dog'
```

![Code editor showing console.log(roger.constructor.name) outputting the string 'Dog'](https://flaviocopes.com/images/javascript-get-object-class-name/Screen_Shot_2022-04-17_at_19.52.41.png)

This method returns a string that represents the class name.

You can also directly compare the `constructor` property to the class, like this:

```js
class Dog {
  
}

const roger = new Dog()

roger.constructor === Dog //true
```

![Code editor showing roger.constructor === Dog comparison returning true](https://flaviocopes.com/images/javascript-get-object-class-name/Screen_Shot_2022-04-17_at_19.54.36.png)