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  1. [ References  ](/en-US/docs/Web)
  2. [ JavaScript  ](/en-US/docs/Web/JavaScript)
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  6. [ Array.prototype.findIndex()  ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/findIndex)

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##  In this article

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

  1. [ Standard built-in objects ](/en-US/docs/Web/JavaScript/Reference/Global_Objects)
  2. [ ` Array ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)
  3. Constructor 
    1. [ ` Array() constructor ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Array)
  4. Properties 
    1. [ ` Array[@@species] ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/@@species)
    2. [ ` Array.prototype[@@unscopables] ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/@@unscopables)
    3. [ ` Array: length ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/length)
  5. Methods 
    1. [ ` Array.prototype[@@iterator]() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/@@iterator)
    2. [ ` Array.prototype.at() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/at)
    3. [ ` Array.prototype.concat() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/concat)
    4. [ ` Array.prototype.copyWithin() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/copyWithin)
    5. [ ` Array.pr