Robtex

Up: 13.33.12.0/22
Can't show all results, try to descend to a more specific CIDR
Down left: 13.33.14.0/24
Down right: 13.33.15.0/24
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
13.33.14.10	A+PTR	server-13-33-14-10.nrt12.r.cloudfront.net
13.33.14.10	A	media.forgecdn.net
13.33.14.10	A	client.forgecdn.net
13.33.14.16	PTR	server-13-33-14-16.iad50.r.cloudfront.net
13.33.14.16	A	bigbiglittle.slack.com
13.33.14.16	A	skygear.slack.com
13.33.14.25	PTR	server-13-33-14-25.iad50.r.cloudfront.net
13.33.14.25	A	server-13-33-14-25.nrt12.r.cloudfront.net
13.33.14.25	A	hypatia-org.slack.com
13.33.14.28	PTR	server-13-33-14-28.nrt12.r.cloudfront.net
13.33.14.28	A	ingress-keihin.slack.com
13.33.14.28	A	fanboat.slack.com
13.33.14.30	PTR	server-13-33-14-30.nrt12.r.cloudfront.net
13.33.14.30	A	crypto-ar.slack.com
13.33.14.30	A	coffeehousecoders.slack.com
13.33.14.33	A+PTR	server-13-33-14-33.nrt12.r.cloudfront.net
13.33.14.33	A	dknq6y19o03a0.cloudfront.net
13.33.14.44	A+PTR	server-13-33-14-44.nrt12.r.cloudfront.net
13.33.14.48	A	ukncsc-external.slack.com
13.33.14.48	A	external.slack.com
13.33.14.52	PTR	server-13-33-14-52.nrt12.r.cloudfront.net
13.33.14.52	A	cryptocatz.slack.com
13.33.14.52	A	fgroupworkspace.slack.com
13.33.14.54	A+PTR	server-13-33-14-54.nrt12.r.cloudfront.net
13.33.14.54	A	d1vx20l4ekviyf.cloudfront.net
13.33.14.55	A+PTR	server-13-33-14-55.nrt12.r.cloudfront.net
13.33.14.55	A	ds6wjjb9r9tty.cloudfront.net
13.33.14.66	A+PTR	server-13-33-14-66.nrt12.r.cloudfront.net
13.33.14.66	A	d25nyp9ftng2of.cloudfront.net
13.33.14.68	A+PTR	server-13-33-14-68.nrt12.r.cloudfront.net
13.33.14.68	A	d3qesot08g926f.cloudfront.net
13.33.14.76	PTR	server-13-33-14-76.iad50.r.cloudfront.net
13.33.14.76	A	d3uo9a4kiyu5sk.cloudfront.net
13.33.14.76	A	server-13-33-14-76.nrt12.r.cloudfront.net
13.33.14.79	PTR	server-13-33-14-79.nrt12.r.cloudfront.net
13.33.14.79	A	cognitive-tech.slack.com
13.33.14.79	A	offtopic-dmz.slack.com
13.33.14.92	PTR	server-13-33-14-92.iad50.r.cloudfront.net
13.33.14.92	A	obedis.slack.com
13.33.14.92	A	cognevo.slack.com
13.33.14.95	A+PTR	server-13-33-14-95.nrt12.r.cloudfront.net
13.33.14.95	A	d2lj0ekr50gxsh.cloudfront.net
13.33.14.105	PTR	server-13-33-14-105.nrt12.r.cloudfront.net
13.33.14.115	A+PTR	server-13-33-14-115.nrt12.r.cloudfront.net
13.33.14.118	A+PTR	server-13-33-14-118.nrt12.r.cloudfront.net
13.33.14.118	A	d3dus35tg5w2pd.cloudfront.net
13.33.14.120	A+PTR	server-13-33-14-120.nrt12.r.cloudfront.net
13.33.14.120	A	d20vr5knkbg79h.cloudfront.net
13.33.14.139	A+PTR	server-13-33-14-139.nrt12.r.cloudfront.net
13.33.14.139	A	dvo2b19ndqhsb.cloudfront.net
13.33.14.147	A+PTR	server-13-33-14-147.nrt12.r.cloudfront.net
13.33.14.147	A	d2ey2oxk21g1vg.cloudfront.net
13.33.14.155	PTR	server-13-33-14-155.nrt12.r.cloudfront.net
13.33.14.155	A	scaphold.slack.com
13.33.14.155	A	moitsd-dnr.slack.com
13.33.14.165	A+PTR	server-13-33-14-165.nrt12.r.cloudfront.net
13.33.14.165	A	d19w7yfcsg8xmi.cloudfront.net
13.33.14.178	PTR	server-13-33-14-178.nrt12.r.cloudfront.net
13.33.14.180	A+PTR	server-13-33-14-180.nrt12.r.cloudfront.net
13.33.14.181	A+PTR	server-13-33-14-181.nrt12.r.cloudfront.net
13.33.14.181	A	az.testnav.com
13.33.14.198	A+PTR	server-13-33-14-198.nrt12.r.cloudfront.net
13.33.14.198	A	d25svsc35nzo5k.cloudfront.net
13.33.14.210	A+PTR	server-13-33-14-210.nrt12.r.cloudfront.net
13.33.14.211	A+PTR	server-13-33-14-211.nrt12.r.cloudfront.net
13.33.14.211	A	d3hc2te5gcbk7o.cloudfront.net
13.33.14.219	A+PTR	server-13-33-14-219.nrt12.r.cloudfront.net
13.33.14.219	A	d2tzm9p537z64d.cloudfront.net
13.33.14.222	A+PTR	server-13-33-14-222.nrt12.r.cloudfront.net
13.33.14.222	A	d1d0cibq5ul603.cloudfront.net
13.33.14.224	A+PTR	server-13-33-14-224.nrt12.r.cloudfront.net
13.33.14.224	A	d2ua3qey5kjhjy.cloudfront.net
13.33.14.227	A+PTR	server-13-33-14-227.nrt12.r.cloudfront.net
13.33.14.227	A	www.bluefinlabs.com
13.33.14.231	A+PTR	server-13-33-14-231.nrt12.r.cloudfront.net
13.33.14.231	A	daumsfgwkxcs9.cloudfront.net
13.33.14.238	PTR	server-13-33-14-238.iad50.r.cloudfront.net
13.33.14.238	A	server-13-33-14-238.nrt12.r.cloudfront.net
13.33.14.253	PTR	server-13-33-14-253.iad50.r.cloudfront.net
13.33.14.253	A	server-13-33-14-253.nrt12.r.cloudfront.net
13.33.14.253	A	iwatsuji.slack.com
13.33.15.114	PTR	server-13-33-15-114.kul50.r.cloudfront.net
13.33.15.118	A+PTR	server-13-33-15-118.kul50.r.cloudfront.net
13.33.15.124	PTR	server-13-33-15-124.kul50.r.cloudfront.net
13.33.15.130	PTR	server-13-33-15-130.kul50.r.cloudfront.net
13.33.15.140	A+PTR	server-13-33-15-140.kul50.r.cloudfront.net
13.33.15.142	A+PTR	server-13-33-15-142.kul50.r.cloudfront.net
13.33.15.154	PTR	server-13-33-15-154.kul50.r.cloudfront.net
13.33.15.192	A+PTR	server-13-33-15-192.kul50.r.cloudfront.net
13.33.15.226	A+PTR	server-13-33-15-226.kul50.r.cloudfront.net