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The contains() method of the DOMTokenList interface returns a Booleantrue if the underlying list contains the given token, otherwise false.




A DOMString representing the token you want to check for the existance of in the list.

Return value

A Booleantrue if the underlying list contains the given token, otherwise false.


In the following example we retrieve the list of classes set on a <span> element as a DOMTokenList using Element.classList. We then test for the existance of "c" in the list, and write the result into the <span>'s Node.textContent.

First, the HTML:

<span class="a b c"></span>

Now the JavaScript:

var span = document.querySelector("span");
var classes = span.classList;
var result = classes.contains("c");
if(result) {
  span.textContent = "The classList contains 'c'";
} else {
   span.textContent = "The classList does not contain 'c'";

The output looks like this:


Specification Status Comment
The definition of 'contains()' in that specification.
Living Standard Initial definition

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support Yes12 Yes10 Yes Yes
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes Yes ? Yes Yes Yes Yes

Document Tags and Contributors

Contributors to this page: fscholz, chrisdavidmills
Last updated by: fscholz,