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  6. [ Object.isExtensible()  ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/isExtensible)

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##  In this article

  * Try it 
  * Syntax 
  * Description 
  * Examples 
  * Specifications 
  * Browser compatibility 
  * See also 

  1. [ Standard built-in objects ](/en-US/docs/Web/JavaScript/Reference/Global_Objects)
  2. [ ` Object ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)
  3. Constructor 
    1. [ ` Object() constructor ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/Object)
  4. Properties 
    1. [ ` Object.prototype.constructor ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/constructor)
    2. [ ` Object.prototype.__proto__ ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/proto) Deprecated 
  5. Methods 
    1. [ ` Object.prototype.__defineGetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__defineGetter__) Deprecated 
    2. [ ` Object.prototype.__defineSetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__defineSetter__) Deprecated 
    3. [ ` Object.prototype.__lookupGetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__lookupGetter__) Deprecated 
    4. [ ` Object.prototype.__lookupSetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Obj