Tryit Editor v2.7

Edit This Code:
<!DOCTYPE html>
<html>
<body>

Birthday: <input type="date" id="myDate" value="2000-05-05">

<p>Click the button to change the default value of the date field.</p>

<button onclick="myFunction()">Try it</button>

<p><strong>Note:</strong> input elements with type="date" are not supported in Internet Explorer or Firefox.</p>

<script>
function myFunction() {
    document.getElementById("myDate").defaultValue = "2014-02-09";
}
</script>

</body>
</html>