Reverse DNS search. Use the reverse DNS search to find all the reverse DNS entries for a particular organisation. Simply enter an organisations domain name example.com to get the results. Currently the results are limited to a maximum of 5000 results - this will typically only be an issue for big Internet services companies and ISP's. About DNS Lookup. DNS Lookup is a browser based network tool that displays DNS records showing publicly for the domain name being queried. DNS Lookup allows you to use public DNS server (Google, Cloudflare, Quad9, OpenDNS, Level3, Verisign, Comodo, Norton, Yandex, NTT, SDNS, CFIEC, Alidns, 114DNS, Hinet, etc.), Specify name server, Authoritative name server, Top-level domain name server, Root