DNS lookupDNS lookup / nslookup / DIG of DNS records. An online tool for DNS lookups. By default recursive lookups querying the authoritative name servers. Lookups on specific DNS resolvers are also possible. Additionally, it will look up secondary records and output a full log of what was done on a technical level.
IP to CIDR calculation tool with subnet info. The reverse, CIDR ranges to IP addresses, is also possible. Last but not least, it includes a tool for refactoring groups of IPs, domain names, and/or other CIDR ranges.
29-02-2024: An IPv6-specific error snuck into the CIDR tool. It has been fixed. I apologize for any inconvenience on this matter. Sorry.