<textarea> maxlength
Display the number of characters remaining in a textarea
by Stephen
HTML
<textarea name="message" rows="4" cols="24" maxlength="100" id="message" placeholder="Message:" style=""></textarea><br/>
<span id="charNum"></span>
JavaScript
$('#message').keyup(function () {
max = this.getAttribute("maxlength");
var len = $(this).val().length;
if (len >= max) {
$('#charNum').text(' you have reached the limit');
} else {
var char = max - len;
$('#charNum').text(char + ' characters left');
}
});