Dig is a DNS lookup utility provided by ISC. This page is a simple web interface for dig.
$ dig 2001:250:3e00::ffff:ffff:ffc1 PTR
; <<>> DiG 9.16.1-Ubuntu <<>> 2001:250:3e00::ffff:ffff:ffc1 PTR
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 20630
;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;2001:250:3e00::ffff:ffff:ffc1. IN PTR
;; AUTHORITY SECTION:
. 86398 IN SOA a.root-servers.net. nstld.verisign-grs.com. 2021030700 1800 900 604800 86400
;; Query time: 3 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Mar 07 11:43:53 UTC 2021
;; MSG SIZE rcvd: 133