Reserved Example Second Level Domain Names

✅ example.com
✅ yourdomain.example

TLDs for Testing & Doc examples
.test
.example
.invalid
.localhost

     ".test" is recommended for use in testing of current or new DNS
     related code.

     ".example" is recommended for use in documentation or as examples.

     ".invalid" is intended for use in online construction of domain
     names that are sure to be invalid and which it is obvious at a
     glance are invalid.

     The ".localhost" TLD has traditionally been statically defined in
     host DNS implementations as having an A record pointing to the
     loop back IP address and is reserved for such use.  Any other use
     would conflict with widely deployed code which assumes this use.