PageLoadingTime is a super-small and super-simple JavaScript document that allows to recive in the console the loading time of your HTML page.
The script should be placed immediately after the <html> tag for optimal performance.
Example:
<!DOCTYPE html>
<html>
<script> /* script here */ </script>
<head> <!-- head here --> </head>
<body> <!-- body here --> </body>
</html>"DOM tree ready at ?ms" is based on the DOMContentLoaded event.
DOMContentLoaded event is fired when the initial HTML document has been loaded and parsed, without waiting for resources to finish loading.
"Page fully loaded at ?ms" is based on the load event.
load event is fired when the whole page has loaded, including all resources such as stylesheets, images and subframes.