bject.getPrototypeOf(obj) === proto; // true
    

###  Non-object coercion

In ES5, it will throw a [ ` TypeError ` ](/en-
US/docs/Web/JavaScript/Reference/Global_Objects/TypeError) exception if the `
obj ` parameter isn't an object. In ES2015, the parameter will be coerced to
an [ ` Object ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)
.

js

    
    
    Object.getPrototypeOf("foo");
    // TypeError: "foo" is not an object (ES5 code)
    Object.getPrototypeOf("foo");
    // String.prototype                  (ES2015 code)
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-object.getprototypeof  ](https://tc39.es/ecma262/multipage/fundamental-
objects.html#sec-object.getprototypeof)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ Polyfill of ` Object.getPrototypeOf ` in ` core-js ` ](https://github.com/zloirock/core-js#ecmascript-object)
  * [ ` Object.prototype.isPrototypeOf() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/isPrototypeOf)
  * [ ` Object.setPrototypeOf() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/setPrototypeOf)
  * [ ` Object.prototype.__proto__ ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/proto)
  * [ ` Reflect.getPrototypeOf() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect/getPrototypeOf)
  * [ Object.getPrototypeOf ](https://johnresig.com/blog/objectgetprototypeof/) by John Resig (2008) 

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