There is a time when regular people need to know how to make secure passwords, I personally wouldn’t use this service as I have no idea if they log the passwords generated with an IP address… They at least generate 3 so they won’t know which one you choose, provide the password over TLS, and they at least provide a good example for people to learn what a good password could look like.

The site is located at https://xkpasswd.net/

If you want to test the strength of the password, you can use https://passwd.gec.im/ and https://www.grc.com/haystack.htm