# The Object isFrozen() method

> Learn how the JavaScript Object.isFrozen() method tells you whether an object is frozen, returning true for any object you passed through Object.freeze().

Author: [Flavio Copes](https://flaviocopes.com/about/) | Published: 2019-04-10 | Topics: [JavaScript](https://flaviocopes.com/tags/js/) | Canonical: https://flaviocopes.com/javascript-object-isfrozen/

Accepts an object as argument, and returns `true` if the object is frozen, `false` otherwise. Objects are frozen when they are return values of the [`Object.freeze()`](https://flaviocopes.com/javascript-object-freeze/) function.

Example:

```js
const dog = {}
dog.breed = 'Siberian Husky'
const myDog = Object.freeze(dog)
Object.isFrozen(dog) //true
Object.isFrozen(myDog) //true
dog === myDog //true
```

In the example, both `dog` and `myDog` are frozen. The argument passed as argument to `Object.freeze()` is mutated, and can't be un-freezed. It's also returned as argument, hence `dog` === `myDog` (it's the same exact object).