Minify your HTML by removing all the unnecessary characters.
Minify your JS by removing all the unnecessary characters.
Get & verify the meta tags of any website.
Get the web-host of a given website.
Check if the URL is banned and marked as safe/unsafe by Google.
Check if the URL is cached or not by Google.
Make sure your passwords are good enough.
Get details of any file type, such as the mime type or last edit date.