Registered domain data from netapi.com for 1,584 TLDs, DNS providers and registrars. Free, no plan needed: compromised domain and IP checks, search in newly registered domains by word, the most popular websites of a country, TLD, registrar and DNS-provider statistics, and the popularity rank of a domain in the NetAPI Top 1M.
With a NetAPI plan: download links for the full list of a zone, the domains registered or deleted in the last 24 hours, all zones at once, or all domains of a DNS provider or a registrar; lists hold domain names (any plan), datasets add nameservers, hosting IP and country, emails and phone numbers to every domain (Plus or Pro). Also domain and IP lookups.