Replace a Class of an Element

To replace a class of an element with a new one, you use the replace() method of the classList property of the element:

element.classList.replace(currentClass,newClass);Code language: CSS (css)

Suppose you have a <div> element as follows:

<div class="primary info">How to replace a class in JS</div>Code language: JavaScript (javascript)

To replace the primary class with the secondary class, you use the following:

const div = document.querySelector('primary');
div.classList.replace('primary','secondary');Code language: JavaScript (javascript)