Below is the code for automatically making an iframe that adjusts the height according to the contents without using a scrollbar.
Code:
<iframe id="myIframe" src="your-page.html" onload="adjustIframeHeight()" style="width:100%; border:none;"></iframe>
<script>
function adjustIframeHeight() {
var iframe = document.getElementById('myIframe');
iframe.style.height = iframe.contentWindow.document.body.scrollHeight + 'px';
}
</script>