<html>
<body>
<form action="demo_form.php" id="numform" oninput="x.value=parseInt(a.value)+parseInt(b.value)">0
<input type="range" id="a" name="a" value="50">100
+<input type="number" id="b" name="b" value="50">
<br><br>
<input type="submit">
</form>
<p>The output element below is outside the form, but still a part of it.</p>
<output form="numform" name="x" for="a b"></output>
<p><b>Note:</b> The form attribute of the output element is not supported in any of the major bowsers.</p>
</body>
</html>