<!DOCTYPE html>
<html>
<head>
<script>
function myFunction(e) {
    x = e.clientX;
    y = e.clientY;
    coor = "Coordinates: (" + x + "," + y + ")";
    document.getElementById("demo").innerHTML = coor
}

function clearCoor() {
    document.getElementById("demo").innerHTML = "";
}
</script>
</head>
<body style="margin:0px;">

<div id="coordiv" style="width:199px;height:99px;border:1px solid" onmousemove="myFunction(event)" onmouseout="clearCoor()"></div>

<p>Mouse over the rectangle above, and get the coordinates of your mouse pointer.</p>

<p id="demo"></p>

</body>
</html>