Robtex

Up: 216.21.12.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 216.21.13.0/25
Down right: 216.21.13.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
216.21.13.10	A	anycast.popads.net
216.21.13.10	A	serve.popads.net
216.21.13.11	A	serve.popads.net
216.21.13.12	A	www.popads.net
216.21.13.12	A	popads.net
216.21.13.13	A	www.popads.net
216.21.13.13	A	popads.net
216.21.13.14	A	zmhwglwmi.com
216.21.13.14	A	jzkznpleaqshdj.com
216.21.13.14	A	hsgatgymg.com
216.21.13.15	A	zmhwglwmi.com
216.21.13.15	A	jzkznpleaqshdj.com
216.21.13.15	A	hsgatgymg.com
216.21.13.16	A	serve.popads.net
216.21.13.17	A	serve.popads.net
216.21.13.18	A	adscore.com
216.21.13.18	A	www.adsco.re
216.21.13.26	A	intellipopup.com
216.21.13.38	PTR	216-21-13-38.customer.totaluptime.net
216.21.13.38	A	sundial-lodge.co.uk
216.21.13.41	PTR	216-21-13-41.customer.totaluptime.net
216.21.13.41	A	www.ukprotectionltd.co.uk
216.21.13.45	A	jones.ccisd.us
216.21.13.45	A	moody.ccisd.us
216.21.13.52	PTR	216-21-13-52.customer.totaluptime.net
216.21.13.52	A	skyzonewinterpass.com
216.21.13.52	A	rockinjumpwinterpass.com
216.21.13.60	PTR	216-21-13-60.customer.totaluptime.net
216.21.13.71	PTR	216-21-13-71.customer.totaluptime.net
216.21.13.71	A	virgingalacticmedical.com
216.21.13.74	A	cfbank.com
216.21.13.94	A	firstpeoples.com