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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.

Network162.3.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
162.3.0.0
Broadcast address
162.3.127.255
First usable
162.3.0.1
Last usable
162.3.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
B (default /16)
As numbers
Hex A2030000 · Integer 2718105600 to 2718138367
Reverse DNS zones
0.3.162.in-addr.arpa
1.3.162.in-addr.arpa
2.3.162.in-addr.arpa
3.3.162.in-addr.arpa
4.3.162.in-addr.arpa
5.3.162.in-addr.arpa
6.3.162.in-addr.arpa
7.3.162.in-addr.arpa
8.3.162.in-addr.arpa
9.3.162.in-addr.arpa
10.3.162.in-addr.arpa
11.3.162.in-addr.arpa
12.3.162.in-addr.arpa
13.3.162.in-addr.arpa
14.3.162.in-addr.arpa
15.3.162.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10100010.00000011.00000000.00000000162.3.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network10100010.00000011.00000000.00000000162.3.0.0
Broadcast10100010.00000011.01111111.11111111162.3.127.255
Split into smaller subnets/28

162.3.0.0/17 makes 2,048 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1162.3.0.0/28162.3.0.1 to 162.3.0.14162.3.0.1514
2162.3.0.16/28162.3.0.17 to 162.3.0.30162.3.0.3114
3162.3.0.32/28162.3.0.33 to 162.3.0.46162.3.0.4714
4162.3.0.48/28162.3.0.49 to 162.3.0.62162.3.0.6314
5162.3.0.64/28162.3.0.65 to 162.3.0.78162.3.0.7914
6162.3.0.80/28162.3.0.81 to 162.3.0.94162.3.0.9514
7162.3.0.96/28162.3.0.97 to 162.3.0.110162.3.0.11114
8162.3.0.112/28162.3.0.113 to 162.3.0.126162.3.0.12714
9162.3.0.128/28162.3.0.129 to 162.3.0.142162.3.0.14314
10162.3.0.144/28162.3.0.145 to 162.3.0.158162.3.0.15914
11162.3.0.160/28162.3.0.161 to 162.3.0.174162.3.0.17514
12162.3.0.176/28162.3.0.177 to 162.3.0.190162.3.0.19114
13162.3.0.192/28162.3.0.193 to 162.3.0.206162.3.0.20714
14162.3.0.208/28162.3.0.209 to 162.3.0.222162.3.0.22314
15162.3.0.224/28162.3.0.225 to 162.3.0.238162.3.0.23914
16162.3.0.240/28162.3.0.241 to 162.3.0.254162.3.0.25514
17162.3.1.0/28162.3.1.1 to 162.3.1.14162.3.1.1514
18162.3.1.16/28162.3.1.17 to 162.3.1.30162.3.1.3114
19162.3.1.32/28162.3.1.33 to 162.3.1.46162.3.1.4714
20162.3.1.48/28162.3.1.49 to 162.3.1.62162.3.1.6314
21162.3.1.64/28162.3.1.65 to 162.3.1.78162.3.1.7914
22162.3.1.80/28162.3.1.81 to 162.3.1.94162.3.1.9514
23162.3.1.96/28162.3.1.97 to 162.3.1.110162.3.1.11114
24162.3.1.112/28162.3.1.113 to 162.3.1.126162.3.1.12714
25162.3.1.128/28162.3.1.129 to 162.3.1.142162.3.1.14314
26162.3.1.144/28162.3.1.145 to 162.3.1.158162.3.1.15914
27162.3.1.160/28162.3.1.161 to 162.3.1.174162.3.1.17514
28162.3.1.176/28162.3.1.177 to 162.3.1.190162.3.1.19114
29162.3.1.192/28162.3.1.193 to 162.3.1.206162.3.1.20714
30162.3.1.208/28162.3.1.209 to 162.3.1.222162.3.1.22314
31162.3.1.224/28162.3.1.225 to 162.3.1.238162.3.1.23914
32162.3.1.240/28162.3.1.241 to 162.3.1.254162.3.1.25514
33162.3.2.0/28162.3.2.1 to 162.3.2.14162.3.2.1514
34162.3.2.16/28162.3.2.17 to 162.3.2.30162.3.2.3114
35162.3.2.32/28162.3.2.33 to 162.3.2.46162.3.2.4714
36162.3.2.48/28162.3.2.49 to 162.3.2.62162.3.2.6314
37162.3.2.64/28162.3.2.65 to 162.3.2.78162.3.2.7914
38162.3.2.80/28162.3.2.81 to 162.3.2.94162.3.2.9514
39162.3.2.96/28162.3.2.97 to 162.3.2.110162.3.2.11114
40162.3.2.112/28162.3.2.113 to 162.3.2.126162.3.2.12714
41162.3.2.128/28162.3.2.129 to 162.3.2.142162.3.2.14314
42162.3.2.144/28162.3.2.145 to 162.3.2.158162.3.2.15914
43162.3.2.160/28162.3.2.161 to 162.3.2.174162.3.2.17514
44162.3.2.176/28162.3.2.177 to 162.3.2.190162.3.2.19114
45162.3.2.192/28162.3.2.193 to 162.3.2.206162.3.2.20714
46162.3.2.208/28162.3.2.209 to 162.3.2.222162.3.2.22314
47162.3.2.224/28162.3.2.225 to 162.3.2.238162.3.2.23914
48162.3.2.240/28162.3.2.241 to 162.3.2.254162.3.2.25514
49162.3.3.0/28162.3.3.1 to 162.3.3.14162.3.3.1514
50162.3.3.16/28162.3.3.17 to 162.3.3.30162.3.3.3114
51162.3.3.32/28162.3.3.33 to 162.3.3.46162.3.3.4714
52162.3.3.48/28162.3.3.49 to 162.3.3.62162.3.3.6314
53162.3.3.64/28162.3.3.65 to 162.3.3.78162.3.3.7914
54162.3.3.80/28162.3.3.81 to 162.3.3.94162.3.3.9514
55162.3.3.96/28162.3.3.97 to 162.3.3.110162.3.3.11114
56162.3.3.112/28162.3.3.113 to 162.3.3.126162.3.3.12714
57162.3.3.128/28162.3.3.129 to 162.3.3.142162.3.3.14314
58162.3.3.144/28162.3.3.145 to 162.3.3.158162.3.3.15914
59162.3.3.160/28162.3.3.161 to 162.3.3.174162.3.3.17514
60162.3.3.176/28162.3.3.177 to 162.3.3.190162.3.3.19114
61162.3.3.192/28162.3.3.193 to 162.3.3.206162.3.3.20714
62162.3.3.208/28162.3.3.209 to 162.3.3.222162.3.3.22314
63162.3.3.224/28162.3.3.225 to 162.3.3.238162.3.3.23914
64162.3.3.240/28162.3.3.241 to 162.3.3.254162.3.3.25514
65162.3.4.0/28162.3.4.1 to 162.3.4.14162.3.4.1514
66162.3.4.16/28162.3.4.17 to 162.3.4.30162.3.4.3114
67162.3.4.32/28162.3.4.33 to 162.3.4.46162.3.4.4714
68162.3.4.48/28162.3.4.49 to 162.3.4.62162.3.4.6314
69162.3.4.64/28162.3.4.65 to 162.3.4.78162.3.4.7914
70162.3.4.80/28162.3.4.81 to 162.3.4.94162.3.4.9514
71162.3.4.96/28162.3.4.97 to 162.3.4.110162.3.4.11114
72162.3.4.112/28162.3.4.113 to 162.3.4.126162.3.4.12714
73162.3.4.128/28162.3.4.129 to 162.3.4.142162.3.4.14314
74162.3.4.144/28162.3.4.145 to 162.3.4.158162.3.4.15914
75162.3.4.160/28162.3.4.161 to 162.3.4.174162.3.4.17514
76162.3.4.176/28162.3.4.177 to 162.3.4.190162.3.4.19114
77162.3.4.192/28162.3.4.193 to 162.3.4.206162.3.4.20714
78162.3.4.208/28162.3.4.209 to 162.3.4.222162.3.4.22314
79162.3.4.224/28162.3.4.225 to 162.3.4.238162.3.4.23914
80162.3.4.240/28162.3.4.241 to 162.3.4.254162.3.4.25514
81162.3.5.0/28162.3.5.1 to 162.3.5.14162.3.5.1514
82162.3.5.16/28162.3.5.17 to 162.3.5.30162.3.5.3114
83162.3.5.32/28162.3.5.33 to 162.3.5.46162.3.5.4714
84162.3.5.48/28162.3.5.49 to 162.3.5.62162.3.5.6314
85162.3.5.64/28162.3.5.65 to 162.3.5.78162.3.5.7914
86162.3.5.80/28162.3.5.81 to 162.3.5.94162.3.5.9514
87162.3.5.96/28162.3.5.97 to 162.3.5.110162.3.5.11114
88162.3.5.112/28162.3.5.113 to 162.3.5.126162.3.5.12714
89162.3.5.128/28162.3.5.129 to 162.3.5.142162.3.5.14314
90162.3.5.144/28162.3.5.145 to 162.3.5.158162.3.5.15914
91162.3.5.160/28162.3.5.161 to 162.3.5.174162.3.5.17514
92162.3.5.176/28162.3.5.177 to 162.3.5.190162.3.5.19114
93162.3.5.192/28162.3.5.193 to 162.3.5.206162.3.5.20714
94162.3.5.208/28162.3.5.209 to 162.3.5.222162.3.5.22314
95162.3.5.224/28162.3.5.225 to 162.3.5.238162.3.5.23914
96162.3.5.240/28162.3.5.241 to 162.3.5.254162.3.5.25514
97162.3.6.0/28162.3.6.1 to 162.3.6.14162.3.6.1514
98162.3.6.16/28162.3.6.17 to 162.3.6.30162.3.6.3114
99162.3.6.32/28162.3.6.33 to 162.3.6.46162.3.6.4714
100162.3.6.48/28162.3.6.49 to 162.3.6.62162.3.6.6314
101162.3.6.64/28162.3.6.65 to 162.3.6.78162.3.6.7914
102162.3.6.80/28162.3.6.81 to 162.3.6.94162.3.6.9514
103162.3.6.96/28162.3.6.97 to 162.3.6.110162.3.6.11114
104162.3.6.112/28162.3.6.113 to 162.3.6.126162.3.6.12714
105162.3.6.128/28162.3.6.129 to 162.3.6.142162.3.6.14314
106162.3.6.144/28162.3.6.145 to 162.3.6.158162.3.6.15914
107162.3.6.160/28162.3.6.161 to 162.3.6.174162.3.6.17514
108162.3.6.176/28162.3.6.177 to 162.3.6.190162.3.6.19114
109162.3.6.192/28162.3.6.193 to 162.3.6.206162.3.6.20714
110162.3.6.208/28162.3.6.209 to 162.3.6.222162.3.6.22314
111162.3.6.224/28162.3.6.225 to 162.3.6.238162.3.6.23914
112162.3.6.240/28162.3.6.241 to 162.3.6.254162.3.6.25514
113162.3.7.0/28162.3.7.1 to 162.3.7.14162.3.7.1514
114162.3.7.16/28162.3.7.17 to 162.3.7.30162.3.7.3114
115162.3.7.32/28162.3.7.33 to 162.3.7.46162.3.7.4714
116162.3.7.48/28162.3.7.49 to 162.3.7.62162.3.7.6314
117162.3.7.64/28162.3.7.65 to 162.3.7.78162.3.7.7914
118162.3.7.80/28162.3.7.81 to 162.3.7.94162.3.7.9514
119162.3.7.96/28162.3.7.97 to 162.3.7.110162.3.7.11114
120162.3.7.112/28162.3.7.113 to 162.3.7.126162.3.7.12714
121162.3.7.128/28162.3.7.129 to 162.3.7.142162.3.7.14314
122162.3.7.144/28162.3.7.145 to 162.3.7.158162.3.7.15914
123162.3.7.160/28162.3.7.161 to 162.3.7.174162.3.7.17514
124162.3.7.176/28162.3.7.177 to 162.3.7.190162.3.7.19114
125162.3.7.192/28162.3.7.193 to 162.3.7.206162.3.7.20714
126162.3.7.208/28162.3.7.209 to 162.3.7.222162.3.7.22314
127162.3.7.224/28162.3.7.225 to 162.3.7.238162.3.7.23914
128162.3.7.240/28162.3.7.241 to 162.3.7.254162.3.7.25514
129162.3.8.0/28162.3.8.1 to 162.3.8.14162.3.8.1514
130162.3.8.16/28162.3.8.17 to 162.3.8.30162.3.8.3114
131162.3.8.32/28162.3.8.33 to 162.3.8.46162.3.8.4714
132162.3.8.48/28162.3.8.49 to 162.3.8.62162.3.8.6314
133162.3.8.64/28162.3.8.65 to 162.3.8.78162.3.8.7914
134162.3.8.80/28162.3.8.81 to 162.3.8.94162.3.8.9514
135162.3.8.96/28162.3.8.97 to 162.3.8.110162.3.8.11114
136162.3.8.112/28162.3.8.113 to 162.3.8.126162.3.8.12714
137162.3.8.128/28162.3.8.129 to 162.3.8.142162.3.8.14314
138162.3.8.144/28162.3.8.145 to 162.3.8.158162.3.8.15914
139162.3.8.160/28162.3.8.161 to 162.3.8.174162.3.8.17514
140162.3.8.176/28162.3.8.177 to 162.3.8.190162.3.8.19114
141162.3.8.192/28162.3.8.193 to 162.3.8.206162.3.8.20714
142162.3.8.208/28162.3.8.209 to 162.3.8.222162.3.8.22314
143162.3.8.224/28162.3.8.225 to 162.3.8.238162.3.8.23914
144162.3.8.240/28162.3.8.241 to 162.3.8.254162.3.8.25514
145162.3.9.0/28162.3.9.1 to 162.3.9.14162.3.9.1514
146162.3.9.16/28162.3.9.17 to 162.3.9.30162.3.9.3114
147162.3.9.32/28162.3.9.33 to 162.3.9.46162.3.9.4714
148162.3.9.48/28162.3.9.49 to 162.3.9.62162.3.9.6314
149162.3.9.64/28162.3.9.65 to 162.3.9.78162.3.9.7914
150162.3.9.80/28162.3.9.81 to 162.3.9.94162.3.9.9514
151162.3.9.96/28162.3.9.97 to 162.3.9.110162.3.9.11114
152162.3.9.112/28162.3.9.113 to 162.3.9.126162.3.9.12714
153162.3.9.128/28162.3.9.129 to 162.3.9.142162.3.9.14314
154162.3.9.144/28162.3.9.145 to 162.3.9.158162.3.9.15914
155162.3.9.160/28162.3.9.161 to 162.3.9.174162.3.9.17514
156162.3.9.176/28162.3.9.177 to 162.3.9.190162.3.9.19114
157162.3.9.192/28162.3.9.193 to 162.3.9.206162.3.9.20714
158162.3.9.208/28162.3.9.209 to 162.3.9.222162.3.9.22314
159162.3.9.224/28162.3.9.225 to 162.3.9.238162.3.9.23914
160162.3.9.240/28162.3.9.241 to 162.3.9.254162.3.9.25514
161162.3.10.0/28162.3.10.1 to 162.3.10.14162.3.10.1514
162162.3.10.16/28162.3.10.17 to 162.3.10.30162.3.10.3114
163162.3.10.32/28162.3.10.33 to 162.3.10.46162.3.10.4714
164162.3.10.48/28162.3.10.49 to 162.3.10.62162.3.10.6314
165162.3.10.64/28162.3.10.65 to 162.3.10.78162.3.10.7914
166162.3.10.80/28162.3.10.81 to 162.3.10.94162.3.10.9514
167162.3.10.96/28162.3.10.97 to 162.3.10.110162.3.10.11114
168162.3.10.112/28162.3.10.113 to 162.3.10.126162.3.10.12714
169162.3.10.128/28162.3.10.129 to 162.3.10.142162.3.10.14314
170162.3.10.144/28162.3.10.145 to 162.3.10.158162.3.10.15914
171162.3.10.160/28162.3.10.161 to 162.3.10.174162.3.10.17514
172162.3.10.176/28162.3.10.177 to 162.3.10.190162.3.10.19114
173162.3.10.192/28162.3.10.193 to 162.3.10.206162.3.10.20714
174162.3.10.208/28162.3.10.209 to 162.3.10.222162.3.10.22314
175162.3.10.224/28162.3.10.225 to 162.3.10.238162.3.10.23914
176162.3.10.240/28162.3.10.241 to 162.3.10.254162.3.10.25514
177162.3.11.0/28162.3.11.1 to 162.3.11.14162.3.11.1514
178162.3.11.16/28162.3.11.17 to 162.3.11.30162.3.11.3114
179162.3.11.32/28162.3.11.33 to 162.3.11.46162.3.11.4714
180162.3.11.48/28162.3.11.49 to 162.3.11.62162.3.11.6314
181162.3.11.64/28162.3.11.65 to 162.3.11.78162.3.11.7914
182162.3.11.80/28162.3.11.81 to 162.3.11.94162.3.11.9514
183162.3.11.96/28162.3.11.97 to 162.3.11.110162.3.11.11114
184162.3.11.112/28162.3.11.113 to 162.3.11.126162.3.11.12714
185162.3.11.128/28162.3.11.129 to 162.3.11.142162.3.11.14314
186162.3.11.144/28162.3.11.145 to 162.3.11.158162.3.11.15914
187162.3.11.160/28162.3.11.161 to 162.3.11.174162.3.11.17514
188162.3.11.176/28162.3.11.177 to 162.3.11.190162.3.11.19114
189162.3.11.192/28162.3.11.193 to 162.3.11.206162.3.11.20714
190162.3.11.208/28162.3.11.209 to 162.3.11.222162.3.11.22314
191162.3.11.224/28162.3.11.225 to 162.3.11.238162.3.11.23914
192162.3.11.240/28162.3.11.241 to 162.3.11.254162.3.11.25514
193162.3.12.0/28162.3.12.1 to 162.3.12.14162.3.12.1514
194162.3.12.16/28162.3.12.17 to 162.3.12.30162.3.12.3114
195162.3.12.32/28162.3.12.33 to 162.3.12.46162.3.12.4714
196162.3.12.48/28162.3.12.49 to 162.3.12.62162.3.12.6314
197162.3.12.64/28162.3.12.65 to 162.3.12.78162.3.12.7914
198162.3.12.80/28162.3.12.81 to 162.3.12.94162.3.12.9514
199162.3.12.96/28162.3.12.97 to 162.3.12.110162.3.12.11114
200162.3.12.112/28162.3.12.113 to 162.3.12.126162.3.12.12714
201162.3.12.128/28162.3.12.129 to 162.3.12.142162.3.12.14314
202162.3.12.144/28162.3.12.145 to 162.3.12.158162.3.12.15914
203162.3.12.160/28162.3.12.161 to 162.3.12.174162.3.12.17514
204162.3.12.176/28162.3.12.177 to 162.3.12.190162.3.12.19114
205162.3.12.192/28162.3.12.193 to 162.3.12.206162.3.12.20714
206162.3.12.208/28162.3.12.209 to 162.3.12.222162.3.12.22314
207162.3.12.224/28162.3.12.225 to 162.3.12.238162.3.12.23914
208162.3.12.240/28162.3.12.241 to 162.3.12.254162.3.12.25514
209162.3.13.0/28162.3.13.1 to 162.3.13.14162.3.13.1514
210162.3.13.16/28162.3.13.17 to 162.3.13.30162.3.13.3114
211162.3.13.32/28162.3.13.33 to 162.3.13.46162.3.13.4714
212162.3.13.48/28162.3.13.49 to 162.3.13.62162.3.13.6314
213162.3.13.64/28162.3.13.65 to 162.3.13.78162.3.13.7914
214162.3.13.80/28162.3.13.81 to 162.3.13.94162.3.13.9514
215162.3.13.96/28162.3.13.97 to 162.3.13.110162.3.13.11114
216162.3.13.112/28162.3.13.113 to 162.3.13.126162.3.13.12714
217162.3.13.128/28162.3.13.129 to 162.3.13.142162.3.13.14314
218162.3.13.144/28162.3.13.145 to 162.3.13.158162.3.13.15914
219162.3.13.160/28162.3.13.161 to 162.3.13.174162.3.13.17514
220162.3.13.176/28162.3.13.177 to 162.3.13.190162.3.13.19114
221162.3.13.192/28162.3.13.193 to 162.3.13.206162.3.13.20714
222162.3.13.208/28162.3.13.209 to 162.3.13.222162.3.13.22314
223162.3.13.224/28162.3.13.225 to 162.3.13.238162.3.13.23914
224162.3.13.240/28162.3.13.241 to 162.3.13.254162.3.13.25514
225162.3.14.0/28162.3.14.1 to 162.3.14.14162.3.14.1514
226162.3.14.16/28162.3.14.17 to 162.3.14.30162.3.14.3114
227162.3.14.32/28162.3.14.33 to 162.3.14.46162.3.14.4714
228162.3.14.48/28162.3.14.49 to 162.3.14.62162.3.14.6314
229162.3.14.64/28162.3.14.65 to 162.3.14.78162.3.14.7914
230162.3.14.80/28162.3.14.81 to 162.3.14.94162.3.14.9514
231162.3.14.96/28162.3.14.97 to 162.3.14.110162.3.14.11114
232162.3.14.112/28162.3.14.113 to 162.3.14.126162.3.14.12714
233162.3.14.128/28162.3.14.129 to 162.3.14.142162.3.14.14314
234162.3.14.144/28162.3.14.145 to 162.3.14.158162.3.14.15914
235162.3.14.160/28162.3.14.161 to 162.3.14.174162.3.14.17514
236162.3.14.176/28162.3.14.177 to 162.3.14.190162.3.14.19114
237162.3.14.192/28162.3.14.193 to 162.3.14.206162.3.14.20714
238162.3.14.208/28162.3.14.209 to 162.3.14.222162.3.14.22314
239162.3.14.224/28162.3.14.225 to 162.3.14.238162.3.14.23914
240162.3.14.240/28162.3.14.241 to 162.3.14.254162.3.14.25514
241162.3.15.0/28162.3.15.1 to 162.3.15.14162.3.15.1514
242162.3.15.16/28162.3.15.17 to 162.3.15.30162.3.15.3114
243162.3.15.32/28162.3.15.33 to 162.3.15.46162.3.15.4714
244162.3.15.48/28162.3.15.49 to 162.3.15.62162.3.15.6314
245162.3.15.64/28162.3.15.65 to 162.3.15.78162.3.15.7914
246162.3.15.80/28162.3.15.81 to 162.3.15.94162.3.15.9514
247162.3.15.96/28162.3.15.97 to 162.3.15.110162.3.15.11114
248162.3.15.112/28162.3.15.113 to 162.3.15.126162.3.15.12714
249162.3.15.128/28162.3.15.129 to 162.3.15.142162.3.15.14314
250162.3.15.144/28162.3.15.145 to 162.3.15.158162.3.15.15914
251162.3.15.160/28162.3.15.161 to 162.3.15.174162.3.15.17514
252162.3.15.176/28162.3.15.177 to 162.3.15.190162.3.15.19114
253162.3.15.192/28162.3.15.193 to 162.3.15.206162.3.15.20714
254162.3.15.208/28162.3.15.209 to 162.3.15.222162.3.15.22314
255162.3.15.224/28162.3.15.225 to 162.3.15.238162.3.15.23914
256162.3.15.240/28162.3.15.241 to 162.3.15.254162.3.15.25514

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