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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/112
Addresses65,536
/64 networksPart of one
Network
::ffff:0.231.0.0/112
First address
::ffff:0.231.0.0
Last address
::ffff:0.231.255.255
Addresses
65,536
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
0000:0000:0000:0000:0000:ffff:00e7:0000
Type
IPv4-mapped ::ffff:0:0/96
An IPv4 address written as IPv6
IPv4 address inside
0.231.0.0
Reverse DNS zone
7.e.0.0.f.f.f.f.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa
Split into smaller subnets/127

::ffff:0.231.0.0/112 makes 32,768 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
1::ffff:0.231.0.0/127::ffff:0.231.0.1
2::ffff:0.231.0.2/127::ffff:0.231.0.3
3::ffff:0.231.0.4/127::ffff:0.231.0.5
4::ffff:0.231.0.6/127::ffff:0.231.0.7
5::ffff:0.231.0.8/127::ffff:0.231.0.9
6::ffff:0.231.0.10/127::ffff:0.231.0.11
7::ffff:0.231.0.12/127::ffff:0.231.0.13
8::ffff:0.231.0.14/127::ffff:0.231.0.15
9::ffff:0.231.0.16/127::ffff:0.231.0.17
10::ffff:0.231.0.18/127::ffff:0.231.0.19
11::ffff:0.231.0.20/127::ffff:0.231.0.21
12::ffff:0.231.0.22/127::ffff:0.231.0.23
13::ffff:0.231.0.24/127::ffff:0.231.0.25
14::ffff:0.231.0.26/127::ffff:0.231.0.27
15::ffff:0.231.0.28/127::ffff:0.231.0.29
16::ffff:0.231.0.30/127::ffff:0.231.0.31
17::ffff:0.231.0.32/127::ffff:0.231.0.33
18::ffff:0.231.0.34/127::ffff:0.231.0.35
19::ffff:0.231.0.36/127::ffff:0.231.0.37
20::ffff:0.231.0.38/127::ffff:0.231.0.39
21::ffff:0.231.0.40/127::ffff:0.231.0.41
22::ffff:0.231.0.42/127::ffff:0.231.0.43
23::ffff:0.231.0.44/127::ffff:0.231.0.45
24::ffff:0.231.0.46/127::ffff:0.231.0.47
25::ffff:0.231.0.48/127::ffff:0.231.0.49
26::ffff:0.231.0.50/127::ffff:0.231.0.51
27::ffff:0.231.0.52/127::ffff:0.231.0.53
28::ffff:0.231.0.54/127::ffff:0.231.0.55
29::ffff:0.231.0.56/127::ffff:0.231.0.57
30::ffff:0.231.0.58/127::ffff:0.231.0.59
31::ffff:0.231.0.60/127::ffff:0.231.0.61
32::ffff:0.231.0.62/127::ffff:0.231.0.63
33::ffff:0.231.0.64/127::ffff:0.231.0.65
34::ffff:0.231.0.66/127::ffff:0.231.0.67
35::ffff:0.231.0.68/127::ffff:0.231.0.69
36::ffff:0.231.0.70/127::ffff:0.231.0.71
37::ffff:0.231.0.72/127::ffff:0.231.0.73
38::ffff:0.231.0.74/127::ffff:0.231.0.75
39::ffff:0.231.0.76/127::ffff:0.231.0.77
40::ffff:0.231.0.78/127::ffff:0.231.0.79
41::ffff:0.231.0.80/127::ffff:0.231.0.81
42::ffff:0.231.0.82/127::ffff:0.231.0.83
43::ffff:0.231.0.84/127::ffff:0.231.0.85
44::ffff:0.231.0.86/127::ffff:0.231.0.87
45::ffff:0.231.0.88/127::ffff:0.231.0.89
46::ffff:0.231.0.90/127::ffff:0.231.0.91
47::ffff:0.231.0.92/127::ffff:0.231.0.93
48::ffff:0.231.0.94/127::ffff:0.231.0.95
49::ffff:0.231.0.96/127::ffff:0.231.0.97
50::ffff:0.231.0.98/127::ffff:0.231.0.99
51::ffff:0.231.0.100/127::ffff:0.231.0.101
52::ffff:0.231.0.102/127::ffff:0.231.0.103
53::ffff:0.231.0.104/127::ffff:0.231.0.105
54::ffff:0.231.0.106/127::ffff:0.231.0.107
55::ffff:0.231.0.108/127::ffff:0.231.0.109
56::ffff:0.231.0.110/127::ffff:0.231.0.111
57::ffff:0.231.0.112/127::ffff:0.231.0.113
58::ffff:0.231.0.114/127::ffff:0.231.0.115
59::ffff:0.231.0.116/127::ffff:0.231.0.117
60::ffff:0.231.0.118/127::ffff:0.231.0.119
61::ffff:0.231.0.120/127::ffff:0.231.0.121
62::ffff:0.231.0.122/127::ffff:0.231.0.123
63::ffff:0.231.0.124/127::ffff:0.231.0.125
64::ffff:0.231.0.126/127::ffff:0.231.0.127
65::ffff:0.231.0.128/127::ffff:0.231.0.129
66::ffff:0.231.0.130/127::ffff:0.231.0.131
67::ffff:0.231.0.132/127::ffff:0.231.0.133
68::ffff:0.231.0.134/127::ffff:0.231.0.135
69::ffff:0.231.0.136/127::ffff:0.231.0.137
70::ffff:0.231.0.138/127::ffff:0.231.0.139
71::ffff:0.231.0.140/127::ffff:0.231.0.141
72::ffff:0.231.0.142/127::ffff:0.231.0.143
73::ffff:0.231.0.144/127::ffff:0.231.0.145
74::ffff:0.231.0.146/127::ffff:0.231.0.147
75::ffff:0.231.0.148/127::ffff:0.231.0.149
76::ffff:0.231.0.150/127::ffff:0.231.0.151
77::ffff:0.231.0.152/127::ffff:0.231.0.153
78::ffff:0.231.0.154/127::ffff:0.231.0.155
79::ffff:0.231.0.156/127::ffff:0.231.0.157
80::ffff:0.231.0.158/127::ffff:0.231.0.159
81::ffff:0.231.0.160/127::ffff:0.231.0.161
82::ffff:0.231.0.162/127::ffff:0.231.0.163
83::ffff:0.231.0.164/127::ffff:0.231.0.165
84::ffff:0.231.0.166/127::ffff:0.231.0.167
85::ffff:0.231.0.168/127::ffff:0.231.0.169
86::ffff:0.231.0.170/127::ffff:0.231.0.171
87::ffff:0.231.0.172/127::ffff:0.231.0.173
88::ffff:0.231.0.174/127::ffff:0.231.0.175
89::ffff:0.231.0.176/127::ffff:0.231.0.177
90::ffff:0.231.0.178/127::ffff:0.231.0.179
91::ffff:0.231.0.180/127::ffff:0.231.0.181
92::ffff:0.231.0.182/127::ffff:0.231.0.183
93::ffff:0.231.0.184/127::ffff:0.231.0.185
94::ffff:0.231.0.186/127::ffff:0.231.0.187
95::ffff:0.231.0.188/127::ffff:0.231.0.189
96::ffff:0.231.0.190/127::ffff:0.231.0.191
97::ffff:0.231.0.192/127::ffff:0.231.0.193
98::ffff:0.231.0.194/127::ffff:0.231.0.195
99::ffff:0.231.0.196/127::ffff:0.231.0.197
100::ffff:0.231.0.198/127::ffff:0.231.0.199
101::ffff:0.231.0.200/127::ffff:0.231.0.201
102::ffff:0.231.0.202/127::ffff:0.231.0.203
103::ffff:0.231.0.204/127::ffff:0.231.0.205
104::ffff:0.231.0.206/127::ffff:0.231.0.207
105::ffff:0.231.0.208/127::ffff:0.231.0.209
106::ffff:0.231.0.210/127::ffff:0.231.0.211
107::ffff:0.231.0.212/127::ffff:0.231.0.213
108::ffff:0.231.0.214/127::ffff:0.231.0.215
109::ffff:0.231.0.216/127::ffff:0.231.0.217
110::ffff:0.231.0.218/127::ffff:0.231.0.219
111::ffff:0.231.0.220/127::ffff:0.231.0.221
112::ffff:0.231.0.222/127::ffff:0.231.0.223
113::ffff:0.231.0.224/127::ffff:0.231.0.225
114::ffff:0.231.0.226/127::ffff:0.231.0.227
115::ffff:0.231.0.228/127::ffff:0.231.0.229
116::ffff:0.231.0.230/127::ffff:0.231.0.231
117::ffff:0.231.0.232/127::ffff:0.231.0.233
118::ffff:0.231.0.234/127::ffff:0.231.0.235
119::ffff:0.231.0.236/127::ffff:0.231.0.237
120::ffff:0.231.0.238/127::ffff:0.231.0.239
121::ffff:0.231.0.240/127::ffff:0.231.0.241
122::ffff:0.231.0.242/127::ffff:0.231.0.243
123::ffff:0.231.0.244/127::ffff:0.231.0.245
124::ffff:0.231.0.246/127::ffff:0.231.0.247
125::ffff:0.231.0.248/127::ffff:0.231.0.249
126::ffff:0.231.0.250/127::ffff:0.231.0.251
127::ffff:0.231.0.252/127::ffff:0.231.0.253
128::ffff:0.231.0.254/127::ffff:0.231.0.255
129::ffff:0.231.1.0/127::ffff:0.231.1.1
130::ffff:0.231.1.2/127::ffff:0.231.1.3
131::ffff:0.231.1.4/127::ffff:0.231.1.5
132::ffff:0.231.1.6/127::ffff:0.231.1.7
133::ffff:0.231.1.8/127::ffff:0.231.1.9
134::ffff:0.231.1.10/127::ffff:0.231.1.11
135::ffff:0.231.1.12/127::ffff:0.231.1.13
136::ffff:0.231.1.14/127::ffff:0.231.1.15
137::ffff:0.231.1.16/127::ffff:0.231.1.17
138::ffff:0.231.1.18/127::ffff:0.231.1.19
139::ffff:0.231.1.20/127::ffff:0.231.1.21
140::ffff:0.231.1.22/127::ffff:0.231.1.23
141::ffff:0.231.1.24/127::ffff:0.231.1.25
142::ffff:0.231.1.26/127::ffff:0.231.1.27
143::ffff:0.231.1.28/127::ffff:0.231.1.29
144::ffff:0.231.1.30/127::ffff:0.231.1.31
145::ffff:0.231.1.32/127::ffff:0.231.1.33
146::ffff:0.231.1.34/127::ffff:0.231.1.35
147::ffff:0.231.1.36/127::ffff:0.231.1.37
148::ffff:0.231.1.38/127::ffff:0.231.1.39
149::ffff:0.231.1.40/127::ffff:0.231.1.41
150::ffff:0.231.1.42/127::ffff:0.231.1.43
151::ffff:0.231.1.44/127::ffff:0.231.1.45
152::ffff:0.231.1.46/127::ffff:0.231.1.47
153::ffff:0.231.1.48/127::ffff:0.231.1.49
154::ffff:0.231.1.50/127::ffff:0.231.1.51
155::ffff:0.231.1.52/127::ffff:0.231.1.53
156::ffff:0.231.1.54/127::ffff:0.231.1.55
157::ffff:0.231.1.56/127::ffff:0.231.1.57
158::ffff:0.231.1.58/127::ffff:0.231.1.59
159::ffff:0.231.1.60/127::ffff:0.231.1.61
160::ffff:0.231.1.62/127::ffff:0.231.1.63
161::ffff:0.231.1.64/127::ffff:0.231.1.65
162::ffff:0.231.1.66/127::ffff:0.231.1.67
163::ffff:0.231.1.68/127::ffff:0.231.1.69
164::ffff:0.231.1.70/127::ffff:0.231.1.71
165::ffff:0.231.1.72/127::ffff:0.231.1.73
166::ffff:0.231.1.74/127::ffff:0.231.1.75
167::ffff:0.231.1.76/127::ffff:0.231.1.77
168::ffff:0.231.1.78/127::ffff:0.231.1.79
169::ffff:0.231.1.80/127::ffff:0.231.1.81
170::ffff:0.231.1.82/127::ffff:0.231.1.83
171::ffff:0.231.1.84/127::ffff:0.231.1.85
172::ffff:0.231.1.86/127::ffff:0.231.1.87
173::ffff:0.231.1.88/127::ffff:0.231.1.89
174::ffff:0.231.1.90/127::ffff:0.231.1.91
175::ffff:0.231.1.92/127::ffff:0.231.1.93
176::ffff:0.231.1.94/127::ffff:0.231.1.95
177::ffff:0.231.1.96/127::ffff:0.231.1.97
178::ffff:0.231.1.98/127::ffff:0.231.1.99
179::ffff:0.231.1.100/127::ffff:0.231.1.101
180::ffff:0.231.1.102/127::ffff:0.231.1.103
181::ffff:0.231.1.104/127::ffff:0.231.1.105
182::ffff:0.231.1.106/127::ffff:0.231.1.107
183::ffff:0.231.1.108/127::ffff:0.231.1.109
184::ffff:0.231.1.110/127::ffff:0.231.1.111
185::ffff:0.231.1.112/127::ffff:0.231.1.113
186::ffff:0.231.1.114/127::ffff:0.231.1.115
187::ffff:0.231.1.116/127::ffff:0.231.1.117
188::ffff:0.231.1.118/127::ffff:0.231.1.119
189::ffff:0.231.1.120/127::ffff:0.231.1.121
190::ffff:0.231.1.122/127::ffff:0.231.1.123
191::ffff:0.231.1.124/127::ffff:0.231.1.125
192::ffff:0.231.1.126/127::ffff:0.231.1.127
193::ffff:0.231.1.128/127::ffff:0.231.1.129
194::ffff:0.231.1.130/127::ffff:0.231.1.131
195::ffff:0.231.1.132/127::ffff:0.231.1.133
196::ffff:0.231.1.134/127::ffff:0.231.1.135
197::ffff:0.231.1.136/127::ffff:0.231.1.137
198::ffff:0.231.1.138/127::ffff:0.231.1.139
199::ffff:0.231.1.140/127::ffff:0.231.1.141
200::ffff:0.231.1.142/127::ffff:0.231.1.143
201::ffff:0.231.1.144/127::ffff:0.231.1.145
202::ffff:0.231.1.146/127::ffff:0.231.1.147
203::ffff:0.231.1.148/127::ffff:0.231.1.149
204::ffff:0.231.1.150/127::ffff:0.231.1.151
205::ffff:0.231.1.152/127::ffff:0.231.1.153
206::ffff:0.231.1.154/127::ffff:0.231.1.155
207::ffff:0.231.1.156/127::ffff:0.231.1.157
208::ffff:0.231.1.158/127::ffff:0.231.1.159
209::ffff:0.231.1.160/127::ffff:0.231.1.161
210::ffff:0.231.1.162/127::ffff:0.231.1.163
211::ffff:0.231.1.164/127::ffff:0.231.1.165
212::ffff:0.231.1.166/127::ffff:0.231.1.167
213::ffff:0.231.1.168/127::ffff:0.231.1.169
214::ffff:0.231.1.170/127::ffff:0.231.1.171
215::ffff:0.231.1.172/127::ffff:0.231.1.173
216::ffff:0.231.1.174/127::ffff:0.231.1.175
217::ffff:0.231.1.176/127::ffff:0.231.1.177
218::ffff:0.231.1.178/127::ffff:0.231.1.179
219::ffff:0.231.1.180/127::ffff:0.231.1.181
220::ffff:0.231.1.182/127::ffff:0.231.1.183
221::ffff:0.231.1.184/127::ffff:0.231.1.185
222::ffff:0.231.1.186/127::ffff:0.231.1.187
223::ffff:0.231.1.188/127::ffff:0.231.1.189
224::ffff:0.231.1.190/127::ffff:0.231.1.191
225::ffff:0.231.1.192/127::ffff:0.231.1.193
226::ffff:0.231.1.194/127::ffff:0.231.1.195
227::ffff:0.231.1.196/127::ffff:0.231.1.197
228::ffff:0.231.1.198/127::ffff:0.231.1.199
229::ffff:0.231.1.200/127::ffff:0.231.1.201
230::ffff:0.231.1.202/127::ffff:0.231.1.203
231::ffff:0.231.1.204/127::ffff:0.231.1.205
232::ffff:0.231.1.206/127::ffff:0.231.1.207
233::ffff:0.231.1.208/127::ffff:0.231.1.209
234::ffff:0.231.1.210/127::ffff:0.231.1.211
235::ffff:0.231.1.212/127::ffff:0.231.1.213
236::ffff:0.231.1.214/127::ffff:0.231.1.215
237::ffff:0.231.1.216/127::ffff:0.231.1.217
238::ffff:0.231.1.218/127::ffff:0.231.1.219
239::ffff:0.231.1.220/127::ffff:0.231.1.221
240::ffff:0.231.1.222/127::ffff:0.231.1.223
241::ffff:0.231.1.224/127::ffff:0.231.1.225
242::ffff:0.231.1.226/127::ffff:0.231.1.227
243::ffff:0.231.1.228/127::ffff:0.231.1.229
244::ffff:0.231.1.230/127::ffff:0.231.1.231
245::ffff:0.231.1.232/127::ffff:0.231.1.233
246::ffff:0.231.1.234/127::ffff:0.231.1.235
247::ffff:0.231.1.236/127::ffff:0.231.1.237
248::ffff:0.231.1.238/127::ffff:0.231.1.239
249::ffff:0.231.1.240/127::ffff:0.231.1.241
250::ffff:0.231.1.242/127::ffff:0.231.1.243
251::ffff:0.231.1.244/127::ffff:0.231.1.245
252::ffff:0.231.1.246/127::ffff:0.231.1.247
253::ffff:0.231.1.248/127::ffff:0.231.1.249
254::ffff:0.231.1.250/127::ffff:0.231.1.251
255::ffff:0.231.1.252/127::ffff:0.231.1.253
256::ffff:0.231.1.254/127::ffff:0.231.1.255

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses