> arr[idx - 1];
      });
    console.log(isIncreasing); // true
    

###  Using every() on sparse arrays

` every() ` will not run its predicate on empty slots.

js

    
    
    console.log([1, , 3].every((x) => x !== undefined)); // true
    console.log([2, , 2].every((x) => x === 2)); // true
    

###  Calling every() on non-array objects

The ` every() ` method reads the ` length ` property of ` this ` and then
accesses each property with a nonnegative integer key less than ` length `
until they all have been accessed or ` callbackFn ` returns ` false ` .

js

    
    
    const arrayLike = {
      length: 3,
      0: "a",
      1: "b",
      2: "c",
      3: 345, // ignored by every() since length is 3
    };
    console.log(
      Array.prototype.every.call(arrayLike, (x) => typeof x === "string"),
    ); // true
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-array.prototype.every  ](https://tc39.es/ecma262/multipage/indexed-
collections.html#sec-array.prototype.every)  
  
##  Browser compatibility

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

##  See also

  * [ Polyfill of ` Array.prototype.every ` in ` core-js ` ](https://github.com/zloirock/core-js#ecmascript-array)
  * [ Indexed collections ](/en-US/docs/Web/JavaScript/Guide/Indexed_collections) guide 
  * [ ` Array ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)
  * [ ` Array.prototype.forEach() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach)
  * [ ` Array.prototype.some() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/some)
  * [ ` Array.prototype.find() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find)
  * [ ` TypedArray.prototype.every() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray/every)

##  Help improve MDN

Was this page helpful to you?

Yes  No

[ Learn how to contribute
](https://github.com/mdn/content/blob/main/CONTRIBUTING.md "This will take you
to our contribution guidelines on GitHub.") .

This page was last modified on  Nov 27, 2023  by  [ MDN contributors ](/en-
US/docs/Web/JavaScript/Reference/Global_Objects/Array/every/contributors.txt)
.

[ View this page on GitHub
](https://github.com/mdn/content/blob/main/files/en-
us/web/javascript/reference/global_objects/array/every/index.md?plain=1
"Folder: en-us/web/javascript/reference/global_objects/array/every \(Opens in
a new tab\)") â¢  [ Report a problem with this content
](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-
url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-
US%2Fdocs%2FWeb%2FJavaScript%2FReference%2FGlobal_Objects%2FArray%2Fevery&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-
us%2Fweb%2Fjavascript%2Freference%2Fglobal_objects%2Farray%2Fevery%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-
US%2Fdocs%2FWeb%2FJavaScript%2FReference%2FGlobal_Objects%2FArray%2Fevery%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-
us%2Fweb%2Fjavascript%2Freference%2Fglobal_objects%2Farray%2Fevery%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F57375b77984037c614982a9327bc96101824db89%0A*+Document+last+modified%3A+2023-11-27T08%3A17%3A23.000Z%0A%0A%3C%2Fdetails%3E
"This will take you to GitHub to file a new issue.")

[ MDN logo  ](/)

Your blueprint for a better internet.

  * [ MDN on Mastodon  ](https://mozilla.social/@mdn)
  * [ MDN on X (formerly Twitter)  ](https://twitter.com/mozdevnet)
  * [ MDN on GitHub  ](https://github.com/mdn/)
  * [ MDN Blog RSS Feed  ](/en-US/blog/rss.xml)

##  MDN

  * [ About ](/en-US/about)
  * [ Blog ](/en-US/blog/)
  * [ Careers ](https://www.mozilla.org/en-US/careers/listings/?team=ProdOps)
  * [ Advertise with us ](/en-US/advertising)

##  Support

  * [ Product help ](https:/