To check if the element has a specific attribute in JavaScript, you can use the hasAttribute() method in the element.

Let's say you have an h1 element with custom attribute data-color="red" like this,

<h1 data-color="red">Heading</h1>

Now let's check is the data-color custom attribute is present in the h1 tag element using the hasAttribute() method in it.

// get the reference to the h1 tag element
const h1 = document.querySelector("h1");

// chcek if h1 tag has attribute : data-color
const isPresent = h1.hasAttribute("data-color");

console.log(isPresent); // true;

• The hasAttribute() method accepts a valid name of the attribute as a string.

• The method return boolean true is present and false is not present.

See live example in JSBin.

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