Dig is a DNS lookup utility provided by ISC. This page is a simple web interface for dig.
$ dig f.root-servers.net ; <<>> DiG 9.11.3-1ubuntu1.3-Ubuntu <<>> f.root-servers.net ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 44359 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 512 ;; QUESTION SECTION: ;f.root-servers.net. IN A ;; ANSWER SECTION: f.root-servers.net. 65909 IN A 192.5.5.241 ;; Query time: 0 msec ;; SERVER: 8.8.8.8#53(8.8.8.8) ;; WHEN: Mon Dec 17 20:29:07 UTC 2018 ;; MSG SIZE rcvd: 63