Getting Started - TinyMCE

HTML

<script src="https://tinymce.cachefly.net/4.2/tinymce.min.js"></script>
<textarea class="tinymce" rows="2" cols="20"></textarea><br />
<div class="character_count"></div>

<textarea class="tinymce" rows="2" cols="20"></textarea><br />
<div class="character_count"></div>

<textarea class="tinymce" rows="2" cols="20"></textarea><br />
<div class="character_count"></div>

JavaScript

tinymce.init({
		selector: '.tinymce',
		width: 400,
		setup: function (ed) {
			ed.on('keyup', function (e) {
				var count = CountCharacters();
				
				$(this).closest(".character_count").text("Characters: " + count); 
				
			});
		}
	});
   
	function CountCharacters() {
		var body = tinymce.activeEditor.getBody();
		var content = tinymce.trim(body.innerText || body.textContent);
		return content.length;
	};