To get the count of child elements inside a parent element, You can use the

childElementCount

property in the DOM element in JavaScript.

Let's say we have a div element with some paragraph elements inside it like this,

<div>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
  <p>I'm a Paragraph</p>
</div>

Now let's get the count of the child paragraph elements using the childElementCount property in the div element.

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

// get the length of children
// inside the div element
const lengthOfChildren = div.childElementCount;

console.log(lengthOfChildren); // 13

See this example live in JSBin.

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