Easily convert days to seconds.
Easily convert days to minutes.
Easily convert days to hours.
Easily convert days to weeks.
Easily convert days to months.
Find A, AAAA, CNAME, MX, NS, TXT, SOA DNS records of a host.
Get approximate IP details.
Get the web-host of a given website.
Get all possible details about an SSL certificate.
Take an IP and try to look for the domain/host associated with it.
Make sure your passwords are good enough.