<input type="range" id="range" min="0" max="100" /><br />
<span id="texte"></span>

<script type="text/javascript">

var range = document.getElementById('range');

var texte = document.getElementById('texte');

texte.innerHTML = range.value + '%';

range.onchange = function(){
texte.innerHTML = range.value + '%';
}

</script>