🍦 Vanilla JavaScript

(function() {
	let elText = document.querySelector( "#text" );
	let elCharacterCount = document.querySelector( "#character-count" );
	let elWordCount = document.querySelector( "#word-count" );
	elText.addEventListener( "input", e =>
	{
		elCharacterCount.innerText = e.target.value.length;
		elWordCount.innerText = e.target.value.trim()
			.split( /\s+/g )
			.length;
	});
})();