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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.

Network150.4.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
150.4.0.0
Broadcast address
150.4.63.255
First usable
150.4.0.1
Last usable
150.4.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
B (default /16)
As numbers
Hex 96040000 · Integer 2516844544 to 2516860927
Reverse DNS zones
0.4.150.in-addr.arpa
1.4.150.in-addr.arpa
2.4.150.in-addr.arpa
3.4.150.in-addr.arpa
4.4.150.in-addr.arpa
5.4.150.in-addr.arpa
6.4.150.in-addr.arpa
7.4.150.in-addr.arpa
8.4.150.in-addr.arpa
9.4.150.in-addr.arpa
10.4.150.in-addr.arpa
11.4.150.in-addr.arpa
12.4.150.in-addr.arpa
13.4.150.in-addr.arpa
14.4.150.in-addr.arpa
15.4.150.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010110.00000100.00000000.00000000150.4.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network10010110.00000100.00000000.00000000150.4.0.0
Broadcast10010110.00000100.00111111.11111111150.4.63.255
Split into smaller subnets/30

150.4.0.0/18 makes 4,096 subnets of /30; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1150.4.0.0/30150.4.0.1 to 150.4.0.2150.4.0.32
2150.4.0.4/30150.4.0.5 to 150.4.0.6150.4.0.72
3150.4.0.8/30150.4.0.9 to 150.4.0.10150.4.0.112
4150.4.0.12/30150.4.0.13 to 150.4.0.14150.4.0.152
5150.4.0.16/30150.4.0.17 to 150.4.0.18150.4.0.192
6150.4.0.20/30150.4.0.21 to 150.4.0.22150.4.0.232
7150.4.0.24/30150.4.0.25 to 150.4.0.26150.4.0.272
8150.4.0.28/30150.4.0.29 to 150.4.0.30150.4.0.312
9150.4.0.32/30150.4.0.33 to 150.4.0.34150.4.0.352
10150.4.0.36/30150.4.0.37 to 150.4.0.38150.4.0.392
11150.4.0.40/30150.4.0.41 to 150.4.0.42150.4.0.432
12150.4.0.44/30150.4.0.45 to 150.4.0.46150.4.0.472
13150.4.0.48/30150.4.0.49 to 150.4.0.50150.4.0.512
14150.4.0.52/30150.4.0.53 to 150.4.0.54150.4.0.552
15150.4.0.56/30150.4.0.57 to 150.4.0.58150.4.0.592
16150.4.0.60/30150.4.0.61 to 150.4.0.62150.4.0.632
17150.4.0.64/30150.4.0.65 to 150.4.0.66150.4.0.672
18150.4.0.68/30150.4.0.69 to 150.4.0.70150.4.0.712
19150.4.0.72/30150.4.0.73 to 150.4.0.74150.4.0.752
20150.4.0.76/30150.4.0.77 to 150.4.0.78150.4.0.792
21150.4.0.80/30150.4.0.81 to 150.4.0.82150.4.0.832
22150.4.0.84/30150.4.0.85 to 150.4.0.86150.4.0.872
23150.4.0.88/30150.4.0.89 to 150.4.0.90150.4.0.912
24150.4.0.92/30150.4.0.93 to 150.4.0.94150.4.0.952
25150.4.0.96/30150.4.0.97 to 150.4.0.98150.4.0.992
26150.4.0.100/30150.4.0.101 to 150.4.0.102150.4.0.1032
27150.4.0.104/30150.4.0.105 to 150.4.0.106150.4.0.1072
28150.4.0.108/30150.4.0.109 to 150.4.0.110150.4.0.1112
29150.4.0.112/30150.4.0.113 to 150.4.0.114150.4.0.1152
30150.4.0.116/30150.4.0.117 to 150.4.0.118150.4.0.1192
31150.4.0.120/30150.4.0.121 to 150.4.0.122150.4.0.1232
32150.4.0.124/30150.4.0.125 to 150.4.0.126150.4.0.1272
33150.4.0.128/30150.4.0.129 to 150.4.0.130150.4.0.1312
34150.4.0.132/30150.4.0.133 to 150.4.0.134150.4.0.1352
35150.4.0.136/30150.4.0.137 to 150.4.0.138150.4.0.1392
36150.4.0.140/30150.4.0.141 to 150.4.0.142150.4.0.1432
37150.4.0.144/30150.4.0.145 to 150.4.0.146150.4.0.1472
38150.4.0.148/30150.4.0.149 to 150.4.0.150150.4.0.1512
39150.4.0.152/30150.4.0.153 to 150.4.0.154150.4.0.1552
40150.4.0.156/30150.4.0.157 to 150.4.0.158150.4.0.1592
41150.4.0.160/30150.4.0.161 to 150.4.0.162150.4.0.1632
42150.4.0.164/30150.4.0.165 to 150.4.0.166150.4.0.1672
43150.4.0.168/30150.4.0.169 to 150.4.0.170150.4.0.1712
44150.4.0.172/30150.4.0.173 to 150.4.0.174150.4.0.1752
45150.4.0.176/30150.4.0.177 to 150.4.0.178150.4.0.1792
46150.4.0.180/30150.4.0.181 to 150.4.0.182150.4.0.1832
47150.4.0.184/30150.4.0.185 to 150.4.0.186150.4.0.1872
48150.4.0.188/30150.4.0.189 to 150.4.0.190150.4.0.1912
49150.4.0.192/30150.4.0.193 to 150.4.0.194150.4.0.1952
50150.4.0.196/30150.4.0.197 to 150.4.0.198150.4.0.1992
51150.4.0.200/30150.4.0.201 to 150.4.0.202150.4.0.2032
52150.4.0.204/30150.4.0.205 to 150.4.0.206150.4.0.2072
53150.4.0.208/30150.4.0.209 to 150.4.0.210150.4.0.2112
54150.4.0.212/30150.4.0.213 to 150.4.0.214150.4.0.2152
55150.4.0.216/30150.4.0.217 to 150.4.0.218150.4.0.2192
56150.4.0.220/30150.4.0.221 to 150.4.0.222150.4.0.2232
57150.4.0.224/30150.4.0.225 to 150.4.0.226150.4.0.2272
58150.4.0.228/30150.4.0.229 to 150.4.0.230150.4.0.2312
59150.4.0.232/30150.4.0.233 to 150.4.0.234150.4.0.2352
60150.4.0.236/30150.4.0.237 to 150.4.0.238150.4.0.2392
61150.4.0.240/30150.4.0.241 to 150.4.0.242150.4.0.2432
62150.4.0.244/30150.4.0.245 to 150.4.0.246150.4.0.2472
63150.4.0.248/30150.4.0.249 to 150.4.0.250150.4.0.2512
64150.4.0.252/30150.4.0.253 to 150.4.0.254150.4.0.2552
65150.4.1.0/30150.4.1.1 to 150.4.1.2150.4.1.32
66150.4.1.4/30150.4.1.5 to 150.4.1.6150.4.1.72
67150.4.1.8/30150.4.1.9 to 150.4.1.10150.4.1.112
68150.4.1.12/30150.4.1.13 to 150.4.1.14150.4.1.152
69150.4.1.16/30150.4.1.17 to 150.4.1.18150.4.1.192
70150.4.1.20/30150.4.1.21 to 150.4.1.22150.4.1.232
71150.4.1.24/30150.4.1.25 to 150.4.1.26150.4.1.272
72150.4.1.28/30150.4.1.29 to 150.4.1.30150.4.1.312
73150.4.1.32/30150.4.1.33 to 150.4.1.34150.4.1.352
74150.4.1.36/30150.4.1.37 to 150.4.1.38150.4.1.392
75150.4.1.40/30150.4.1.41 to 150.4.1.42150.4.1.432
76150.4.1.44/30150.4.1.45 to 150.4.1.46150.4.1.472
77150.4.1.48/30150.4.1.49 to 150.4.1.50150.4.1.512
78150.4.1.52/30150.4.1.53 to 150.4.1.54150.4.1.552
79150.4.1.56/30150.4.1.57 to 150.4.1.58150.4.1.592
80150.4.1.60/30150.4.1.61 to 150.4.1.62150.4.1.632
81150.4.1.64/30150.4.1.65 to 150.4.1.66150.4.1.672
82150.4.1.68/30150.4.1.69 to 150.4.1.70150.4.1.712
83150.4.1.72/30150.4.1.73 to 150.4.1.74150.4.1.752
84150.4.1.76/30150.4.1.77 to 150.4.1.78150.4.1.792
85150.4.1.80/30150.4.1.81 to 150.4.1.82150.4.1.832
86150.4.1.84/30150.4.1.85 to 150.4.1.86150.4.1.872
87150.4.1.88/30150.4.1.89 to 150.4.1.90150.4.1.912
88150.4.1.92/30150.4.1.93 to 150.4.1.94150.4.1.952
89150.4.1.96/30150.4.1.97 to 150.4.1.98150.4.1.992
90150.4.1.100/30150.4.1.101 to 150.4.1.102150.4.1.1032
91150.4.1.104/30150.4.1.105 to 150.4.1.106150.4.1.1072
92150.4.1.108/30150.4.1.109 to 150.4.1.110150.4.1.1112
93150.4.1.112/30150.4.1.113 to 150.4.1.114150.4.1.1152
94150.4.1.116/30150.4.1.117 to 150.4.1.118150.4.1.1192
95150.4.1.120/30150.4.1.121 to 150.4.1.122150.4.1.1232
96150.4.1.124/30150.4.1.125 to 150.4.1.126150.4.1.1272
97150.4.1.128/30150.4.1.129 to 150.4.1.130150.4.1.1312
98150.4.1.132/30150.4.1.133 to 150.4.1.134150.4.1.1352
99150.4.1.136/30150.4.1.137 to 150.4.1.138150.4.1.1392
100150.4.1.140/30150.4.1.141 to 150.4.1.142150.4.1.1432
101150.4.1.144/30150.4.1.145 to 150.4.1.146150.4.1.1472
102150.4.1.148/30150.4.1.149 to 150.4.1.150150.4.1.1512
103150.4.1.152/30150.4.1.153 to 150.4.1.154150.4.1.1552
104150.4.1.156/30150.4.1.157 to 150.4.1.158150.4.1.1592
105150.4.1.160/30150.4.1.161 to 150.4.1.162150.4.1.1632
106150.4.1.164/30150.4.1.165 to 150.4.1.166150.4.1.1672
107150.4.1.168/30150.4.1.169 to 150.4.1.170150.4.1.1712
108150.4.1.172/30150.4.1.173 to 150.4.1.174150.4.1.1752
109150.4.1.176/30150.4.1.177 to 150.4.1.178150.4.1.1792
110150.4.1.180/30150.4.1.181 to 150.4.1.182150.4.1.1832
111150.4.1.184/30150.4.1.185 to 150.4.1.186150.4.1.1872
112150.4.1.188/30150.4.1.189 to 150.4.1.190150.4.1.1912
113150.4.1.192/30150.4.1.193 to 150.4.1.194150.4.1.1952
114150.4.1.196/30150.4.1.197 to 150.4.1.198150.4.1.1992
115150.4.1.200/30150.4.1.201 to 150.4.1.202150.4.1.2032
116150.4.1.204/30150.4.1.205 to 150.4.1.206150.4.1.2072
117150.4.1.208/30150.4.1.209 to 150.4.1.210150.4.1.2112
118150.4.1.212/30150.4.1.213 to 150.4.1.214150.4.1.2152
119150.4.1.216/30150.4.1.217 to 150.4.1.218150.4.1.2192
120150.4.1.220/30150.4.1.221 to 150.4.1.222150.4.1.2232
121150.4.1.224/30150.4.1.225 to 150.4.1.226150.4.1.2272
122150.4.1.228/30150.4.1.229 to 150.4.1.230150.4.1.2312
123150.4.1.232/30150.4.1.233 to 150.4.1.234150.4.1.2352
124150.4.1.236/30150.4.1.237 to 150.4.1.238150.4.1.2392
125150.4.1.240/30150.4.1.241 to 150.4.1.242150.4.1.2432
126150.4.1.244/30150.4.1.245 to 150.4.1.246150.4.1.2472
127150.4.1.248/30150.4.1.249 to 150.4.1.250150.4.1.2512
128150.4.1.252/30150.4.1.253 to 150.4.1.254150.4.1.2552
129150.4.2.0/30150.4.2.1 to 150.4.2.2150.4.2.32
130150.4.2.4/30150.4.2.5 to 150.4.2.6150.4.2.72
131150.4.2.8/30150.4.2.9 to 150.4.2.10150.4.2.112
132150.4.2.12/30150.4.2.13 to 150.4.2.14150.4.2.152
133150.4.2.16/30150.4.2.17 to 150.4.2.18150.4.2.192
134150.4.2.20/30150.4.2.21 to 150.4.2.22150.4.2.232
135150.4.2.24/30150.4.2.25 to 150.4.2.26150.4.2.272
136150.4.2.28/30150.4.2.29 to 150.4.2.30150.4.2.312
137150.4.2.32/30150.4.2.33 to 150.4.2.34150.4.2.352
138150.4.2.36/30150.4.2.37 to 150.4.2.38150.4.2.392
139150.4.2.40/30150.4.2.41 to 150.4.2.42150.4.2.432
140150.4.2.44/30150.4.2.45 to 150.4.2.46150.4.2.472
141150.4.2.48/30150.4.2.49 to 150.4.2.50150.4.2.512
142150.4.2.52/30150.4.2.53 to 150.4.2.54150.4.2.552
143150.4.2.56/30150.4.2.57 to 150.4.2.58150.4.2.592
144150.4.2.60/30150.4.2.61 to 150.4.2.62150.4.2.632
145150.4.2.64/30150.4.2.65 to 150.4.2.66150.4.2.672
146150.4.2.68/30150.4.2.69 to 150.4.2.70150.4.2.712
147150.4.2.72/30150.4.2.73 to 150.4.2.74150.4.2.752
148150.4.2.76/30150.4.2.77 to 150.4.2.78150.4.2.792
149150.4.2.80/30150.4.2.81 to 150.4.2.82150.4.2.832
150150.4.2.84/30150.4.2.85 to 150.4.2.86150.4.2.872
151150.4.2.88/30150.4.2.89 to 150.4.2.90150.4.2.912
152150.4.2.92/30150.4.2.93 to 150.4.2.94150.4.2.952
153150.4.2.96/30150.4.2.97 to 150.4.2.98150.4.2.992
154150.4.2.100/30150.4.2.101 to 150.4.2.102150.4.2.1032
155150.4.2.104/30150.4.2.105 to 150.4.2.106150.4.2.1072
156150.4.2.108/30150.4.2.109 to 150.4.2.110150.4.2.1112
157150.4.2.112/30150.4.2.113 to 150.4.2.114150.4.2.1152
158150.4.2.116/30150.4.2.117 to 150.4.2.118150.4.2.1192
159150.4.2.120/30150.4.2.121 to 150.4.2.122150.4.2.1232
160150.4.2.124/30150.4.2.125 to 150.4.2.126150.4.2.1272
161150.4.2.128/30150.4.2.129 to 150.4.2.130150.4.2.1312
162150.4.2.132/30150.4.2.133 to 150.4.2.134150.4.2.1352
163150.4.2.136/30150.4.2.137 to 150.4.2.138150.4.2.1392
164150.4.2.140/30150.4.2.141 to 150.4.2.142150.4.2.1432
165150.4.2.144/30150.4.2.145 to 150.4.2.146150.4.2.1472
166150.4.2.148/30150.4.2.149 to 150.4.2.150150.4.2.1512
167150.4.2.152/30150.4.2.153 to 150.4.2.154150.4.2.1552
168150.4.2.156/30150.4.2.157 to 150.4.2.158150.4.2.1592
169150.4.2.160/30150.4.2.161 to 150.4.2.162150.4.2.1632
170150.4.2.164/30150.4.2.165 to 150.4.2.166150.4.2.1672
171150.4.2.168/30150.4.2.169 to 150.4.2.170150.4.2.1712
172150.4.2.172/30150.4.2.173 to 150.4.2.174150.4.2.1752
173150.4.2.176/30150.4.2.177 to 150.4.2.178150.4.2.1792
174150.4.2.180/30150.4.2.181 to 150.4.2.182150.4.2.1832
175150.4.2.184/30150.4.2.185 to 150.4.2.186150.4.2.1872
176150.4.2.188/30150.4.2.189 to 150.4.2.190150.4.2.1912
177150.4.2.192/30150.4.2.193 to 150.4.2.194150.4.2.1952
178150.4.2.196/30150.4.2.197 to 150.4.2.198150.4.2.1992
179150.4.2.200/30150.4.2.201 to 150.4.2.202150.4.2.2032
180150.4.2.204/30150.4.2.205 to 150.4.2.206150.4.2.2072
181150.4.2.208/30150.4.2.209 to 150.4.2.210150.4.2.2112
182150.4.2.212/30150.4.2.213 to 150.4.2.214150.4.2.2152
183150.4.2.216/30150.4.2.217 to 150.4.2.218150.4.2.2192
184150.4.2.220/30150.4.2.221 to 150.4.2.222150.4.2.2232
185150.4.2.224/30150.4.2.225 to 150.4.2.226150.4.2.2272
186150.4.2.228/30150.4.2.229 to 150.4.2.230150.4.2.2312
187150.4.2.232/30150.4.2.233 to 150.4.2.234150.4.2.2352
188150.4.2.236/30150.4.2.237 to 150.4.2.238150.4.2.2392
189150.4.2.240/30150.4.2.241 to 150.4.2.242150.4.2.2432
190150.4.2.244/30150.4.2.245 to 150.4.2.246150.4.2.2472
191150.4.2.248/30150.4.2.249 to 150.4.2.250150.4.2.2512
192150.4.2.252/30150.4.2.253 to 150.4.2.254150.4.2.2552
193150.4.3.0/30150.4.3.1 to 150.4.3.2150.4.3.32
194150.4.3.4/30150.4.3.5 to 150.4.3.6150.4.3.72
195150.4.3.8/30150.4.3.9 to 150.4.3.10150.4.3.112
196150.4.3.12/30150.4.3.13 to 150.4.3.14150.4.3.152
197150.4.3.16/30150.4.3.17 to 150.4.3.18150.4.3.192
198150.4.3.20/30150.4.3.21 to 150.4.3.22150.4.3.232
199150.4.3.24/30150.4.3.25 to 150.4.3.26150.4.3.272
200150.4.3.28/30150.4.3.29 to 150.4.3.30150.4.3.312
201150.4.3.32/30150.4.3.33 to 150.4.3.34150.4.3.352
202150.4.3.36/30150.4.3.37 to 150.4.3.38150.4.3.392
203150.4.3.40/30150.4.3.41 to 150.4.3.42150.4.3.432
204150.4.3.44/30150.4.3.45 to 150.4.3.46150.4.3.472
205150.4.3.48/30150.4.3.49 to 150.4.3.50150.4.3.512
206150.4.3.52/30150.4.3.53 to 150.4.3.54150.4.3.552
207150.4.3.56/30150.4.3.57 to 150.4.3.58150.4.3.592
208150.4.3.60/30150.4.3.61 to 150.4.3.62150.4.3.632
209150.4.3.64/30150.4.3.65 to 150.4.3.66150.4.3.672
210150.4.3.68/30150.4.3.69 to 150.4.3.70150.4.3.712
211150.4.3.72/30150.4.3.73 to 150.4.3.74150.4.3.752
212150.4.3.76/30150.4.3.77 to 150.4.3.78150.4.3.792
213150.4.3.80/30150.4.3.81 to 150.4.3.82150.4.3.832
214150.4.3.84/30150.4.3.85 to 150.4.3.86150.4.3.872
215150.4.3.88/30150.4.3.89 to 150.4.3.90150.4.3.912
216150.4.3.92/30150.4.3.93 to 150.4.3.94150.4.3.952
217150.4.3.96/30150.4.3.97 to 150.4.3.98150.4.3.992
218150.4.3.100/30150.4.3.101 to 150.4.3.102150.4.3.1032
219150.4.3.104/30150.4.3.105 to 150.4.3.106150.4.3.1072
220150.4.3.108/30150.4.3.109 to 150.4.3.110150.4.3.1112
221150.4.3.112/30150.4.3.113 to 150.4.3.114150.4.3.1152
222150.4.3.116/30150.4.3.117 to 150.4.3.118150.4.3.1192
223150.4.3.120/30150.4.3.121 to 150.4.3.122150.4.3.1232
224150.4.3.124/30150.4.3.125 to 150.4.3.126150.4.3.1272
225150.4.3.128/30150.4.3.129 to 150.4.3.130150.4.3.1312
226150.4.3.132/30150.4.3.133 to 150.4.3.134150.4.3.1352
227150.4.3.136/30150.4.3.137 to 150.4.3.138150.4.3.1392
228150.4.3.140/30150.4.3.141 to 150.4.3.142150.4.3.1432
229150.4.3.144/30150.4.3.145 to 150.4.3.146150.4.3.1472
230150.4.3.148/30150.4.3.149 to 150.4.3.150150.4.3.1512
231150.4.3.152/30150.4.3.153 to 150.4.3.154150.4.3.1552
232150.4.3.156/30150.4.3.157 to 150.4.3.158150.4.3.1592
233150.4.3.160/30150.4.3.161 to 150.4.3.162150.4.3.1632
234150.4.3.164/30150.4.3.165 to 150.4.3.166150.4.3.1672
235150.4.3.168/30150.4.3.169 to 150.4.3.170150.4.3.1712
236150.4.3.172/30150.4.3.173 to 150.4.3.174150.4.3.1752
237150.4.3.176/30150.4.3.177 to 150.4.3.178150.4.3.1792
238150.4.3.180/30150.4.3.181 to 150.4.3.182150.4.3.1832
239150.4.3.184/30150.4.3.185 to 150.4.3.186150.4.3.1872
240150.4.3.188/30150.4.3.189 to 150.4.3.190150.4.3.1912
241150.4.3.192/30150.4.3.193 to 150.4.3.194150.4.3.1952
242150.4.3.196/30150.4.3.197 to 150.4.3.198150.4.3.1992
243150.4.3.200/30150.4.3.201 to 150.4.3.202150.4.3.2032
244150.4.3.204/30150.4.3.205 to 150.4.3.206150.4.3.2072
245150.4.3.208/30150.4.3.209 to 150.4.3.210150.4.3.2112
246150.4.3.212/30150.4.3.213 to 150.4.3.214150.4.3.2152
247150.4.3.216/30150.4.3.217 to 150.4.3.218150.4.3.2192
248150.4.3.220/30150.4.3.221 to 150.4.3.222150.4.3.2232
249150.4.3.224/30150.4.3.225 to 150.4.3.226150.4.3.2272
250150.4.3.228/30150.4.3.229 to 150.4.3.230150.4.3.2312
251150.4.3.232/30150.4.3.233 to 150.4.3.234150.4.3.2352
252150.4.3.236/30150.4.3.237 to 150.4.3.238150.4.3.2392
253150.4.3.240/30150.4.3.241 to 150.4.3.242150.4.3.2432
254150.4.3.244/30150.4.3.245 to 150.4.3.246150.4.3.2472
255150.4.3.248/30150.4.3.249 to 150.4.3.250150.4.3.2512
256150.4.3.252/30150.4.3.253 to 150.4.3.254150.4.3.2552

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