231.18.4 is a class C of IPs

Sample IPs from the class C 231.18.4

231.18.4.15	View precise location of 231.18.4.15 on the map!
231.18.4.59	View precise location of 231.18.4.59 on the map!
231.18.4.65	View precise location of 231.18.4.65 on the map!
231.18.4.175	View precise location of 231.18.4.175 on the map!
231.18.4.168	View precise location of 231.18.4.168 on the map!
231.18.4.137	View precise location of 231.18.4.137 on the map!
231.18.4.176	View precise location of 231.18.4.176 on the map!
231.18.4.137	View precise location of 231.18.4.137 on the map!
231.18.4.178	View precise location of 231.18.4.178 on the map!
231.18.4.171	View precise location of 231.18.4.171 on the map!
231.18.4.241	View precise location of 231.18.4.241 on the map!

10 Random IPs

27.227.95.180	Find precise map location of 27.227.95.180
145.189.227.79	Find precise map location of 145.189.227.79
45.125.70.80	Find precise map location of 45.125.70.80
153.151.238.65	Find precise map location of 153.151.238.65
204.245.26.232	Find precise map location of 204.245.26.232
35.95.53.129	Find precise map location of 35.95.53.129
243.229.191.176	Find precise map location of 243.229.191.176
61.54.49.119	Find precise map location of 61.54.49.119
72.238.216.220	Find precise map location of 72.238.216.220
207.39.10.222	Find precise map location of 207.39.10.222
65.3.165.2	Find precise map location of 65.3.165.2

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