Fra input til span.

JScript kode 

 <script language="JavaScript">
     function textCounter(Besked, countfield, maxlimit) {
     if (Besked.value.length > maxlimit) 
     Besked.value = Besked.value.substring(0, maxlimit);
     else 
     countfield.value = maxlimit - Besked.value.length;
     }
     </script>

HTML kode 

 maxlength="250" wrap=physical onKeyDown="textCounter(this.form.Besked,this.form.remLen,250);" 
     onKeyUp="textCounter(this.form.Besked,this.form.remLen,250);"></textarea><br />