Pure javascript

• The HTML page with some words to count

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aliquam quis neque nibh. Fusce vitae sapien tincidunt, facilisis risus id, vulputate erat. Ut eget ex sem. Donec ornare consequat risus. Fusce cursus non lorem eu pharetra. Quisque in tristique orci. Nunc luctus turpis id augue euismod volutpat. Morbi ut nunc maximus, rhoncus ante at, feugiat nunc.

• The count function

function countWords(node){
   const text = node.innerText || node.textContent;
   return text.split(/\s+/g).length;
}

• The main: we select the body node and count the words.

node = document.querySelector('body');
console.log("The total number of words is "+countWords(node))

• Result:

Custom Element

See the custom element example