21.166.81 is a class C of IPs

Sample IPs from the class C 21.166.81

21.166.81.68	View precise location of 21.166.81.68 on the map!
21.166.81.44	View precise location of 21.166.81.44 on the map!
21.166.81.123	View precise location of 21.166.81.123 on the map!
21.166.81.49	View precise location of 21.166.81.49 on the map!
21.166.81.144	View precise location of 21.166.81.144 on the map!
21.166.81.120	View precise location of 21.166.81.120 on the map!
21.166.81.111	View precise location of 21.166.81.111 on the map!
21.166.81.79	View precise location of 21.166.81.79 on the map!
21.166.81.48	View precise location of 21.166.81.48 on the map!
21.166.81.33	View precise location of 21.166.81.33 on the map!
21.166.81.51	View precise location of 21.166.81.51 on the map!

10 Random IPs

230.22.197.189	Find precise map location of 230.22.197.189
56.198.170.101	Find precise map location of 56.198.170.101
146.208.199.172	Find precise map location of 146.208.199.172
239.24.181.146	Find precise map location of 239.24.181.146
120.103.150.109	Find precise map location of 120.103.150.109
145.244.88.76	Find precise map location of 145.244.88.76
174.242.63.232	Find precise map location of 174.242.63.232
96.190.20.173	Find precise map location of 96.190.20.173
252.160.42.113	Find precise map location of 252.160.42.113
53.45.31.53	Find precise map location of 53.45.31.53
68.237.98.81	Find precise map location of 68.237.98.81

TestURI.org is a free web-sniffer.net alternative. It alows you to send custom HTTP request and check the HTTP response.