What this tool checks
RDAP is the modern, structured replacement for WHOIS. This tool finds the registry responsible for the domain's TLD through the IANA bootstrap file, queries it directly, and shows the registration and expiry dates, registrar, status codes and nameservers. For TLDs without RDAP it falls back to a WHOIS query, which can only provide an expiry date. Subdomains are looked up as their registrable domain (www.example.com → example.com).
Why domain expiry deserves its own alert
A lapsed domain takes down the website, email and every certificate renewal that depends on DNS validation at once. Registrars send reminders to a contact address that is often no longer monitored. NetworkAI checks registration expiry daily alongside the certificate.