Upload a QR code image and extract the data out of it.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Make sure your passwords are good enough.
Check if the URL is banned and marked as safe/unsafe by Google.
Get the web-host of a given website.
Get all possible details about a domain name.
Get & verify the meta tags of any website.