CPI Domain is a corporate-focused domain registration service from KDDI Web Communications Inc., part of the KDDI Group. It supports .jp, business-type JP domains like .co.jp and .or.jp, and common extensions such as .com, with a focus on companies that want domains and servers managed in one place.

The service works hand-in-hand with CPI rental servers, bringing domains, DNS, SSL certificates, and hosting under a single dashboard. A paid DNS option is available where CPI staff handle record changes on behalf of the customer, which suits companies that prefer not to manage DNS themselves. Companies can also reserve .co.jp domains before they are officially incorporated.