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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.

Network162.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
162.0.0.0
Broadcast address
162.255.255.255
First usable
162.0.0.1
Last usable
162.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
B (default /16)
As numbers
Hex A2000000 · Integer 2717908992 to 2734686207
Reverse DNS zone
162.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10100010..00000000.00000000.00000000162.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10100010..00000000.00000000.00000000162.0.0.0
Broadcast10100010..11111111.11111111.11111111162.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

162.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1162.0.0.0/16162.0.0.1 to 162.0.255.254162.0.255.25565,534
2162.1.0.0/16162.1.0.1 to 162.1.255.254162.1.255.25565,534
3162.2.0.0/16162.2.0.1 to 162.2.255.254162.2.255.25565,534
4162.3.0.0/16162.3.0.1 to 162.3.255.254162.3.255.25565,534
5162.4.0.0/16162.4.0.1 to 162.4.255.254162.4.255.25565,534
6162.5.0.0/16162.5.0.1 to 162.5.255.254162.5.255.25565,534
7162.6.0.0/16162.6.0.1 to 162.6.255.254162.6.255.25565,534
8162.7.0.0/16162.7.0.1 to 162.7.255.254162.7.255.25565,534
9162.8.0.0/16162.8.0.1 to 162.8.255.254162.8.255.25565,534
10162.9.0.0/16162.9.0.1 to 162.9.255.254162.9.255.25565,534
11162.10.0.0/16162.10.0.1 to 162.10.255.254162.10.255.25565,534
12162.11.0.0/16162.11.0.1 to 162.11.255.254162.11.255.25565,534
13162.12.0.0/16162.12.0.1 to 162.12.255.254162.12.255.25565,534
14162.13.0.0/16162.13.0.1 to 162.13.255.254162.13.255.25565,534
15162.14.0.0/16162.14.0.1 to 162.14.255.254162.14.255.25565,534
16162.15.0.0/16162.15.0.1 to 162.15.255.254162.15.255.25565,534
17162.16.0.0/16162.16.0.1 to 162.16.255.254162.16.255.25565,534
18162.17.0.0/16162.17.0.1 to 162.17.255.254162.17.255.25565,534
19162.18.0.0/16162.18.0.1 to 162.18.255.254162.18.255.25565,534
20162.19.0.0/16162.19.0.1 to 162.19.255.254162.19.255.25565,534
21162.20.0.0/16162.20.0.1 to 162.20.255.254162.20.255.25565,534
22162.21.0.0/16162.21.0.1 to 162.21.255.254162.21.255.25565,534
23162.22.0.0/16162.22.0.1 to 162.22.255.254162.22.255.25565,534
24162.23.0.0/16162.23.0.1 to 162.23.255.254162.23.255.25565,534
25162.24.0.0/16162.24.0.1 to 162.24.255.254162.24.255.25565,534
26162.25.0.0/16162.25.0.1 to 162.25.255.254162.25.255.25565,534
27162.26.0.0/16162.26.0.1 to 162.26.255.254162.26.255.25565,534
28162.27.0.0/16162.27.0.1 to 162.27.255.254162.27.255.25565,534
29162.28.0.0/16162.28.0.1 to 162.28.255.254162.28.255.25565,534
30162.29.0.0/16162.29.0.1 to 162.29.255.254162.29.255.25565,534
31162.30.0.0/16162.30.0.1 to 162.30.255.254162.30.255.25565,534
32162.31.0.0/16162.31.0.1 to 162.31.255.254162.31.255.25565,534
33162.32.0.0/16162.32.0.1 to 162.32.255.254162.32.255.25565,534
34162.33.0.0/16162.33.0.1 to 162.33.255.254162.33.255.25565,534
35162.34.0.0/16162.34.0.1 to 162.34.255.254162.34.255.25565,534
36162.35.0.0/16162.35.0.1 to 162.35.255.254162.35.255.25565,534
37162.36.0.0/16162.36.0.1 to 162.36.255.254162.36.255.25565,534
38162.37.0.0/16162.37.0.1 to 162.37.255.254162.37.255.25565,534
39162.38.0.0/16162.38.0.1 to 162.38.255.254162.38.255.25565,534
40162.39.0.0/16162.39.0.1 to 162.39.255.254162.39.255.25565,534
41162.40.0.0/16162.40.0.1 to 162.40.255.254162.40.255.25565,534
42162.41.0.0/16162.41.0.1 to 162.41.255.254162.41.255.25565,534
43162.42.0.0/16162.42.0.1 to 162.42.255.254162.42.255.25565,534
44162.43.0.0/16162.43.0.1 to 162.43.255.254162.43.255.25565,534
45162.44.0.0/16162.44.0.1 to 162.44.255.254162.44.255.25565,534
46162.45.0.0/16162.45.0.1 to 162.45.255.254162.45.255.25565,534
47162.46.0.0/16162.46.0.1 to 162.46.255.254162.46.255.25565,534
48162.47.0.0/16162.47.0.1 to 162.47.255.254162.47.255.25565,534
49162.48.0.0/16162.48.0.1 to 162.48.255.254162.48.255.25565,534
50162.49.0.0/16162.49.0.1 to 162.49.255.254162.49.255.25565,534
51162.50.0.0/16162.50.0.1 to 162.50.255.254162.50.255.25565,534
52162.51.0.0/16162.51.0.1 to 162.51.255.254162.51.255.25565,534
53162.52.0.0/16162.52.0.1 to 162.52.255.254162.52.255.25565,534
54162.53.0.0/16162.53.0.1 to 162.53.255.254162.53.255.25565,534
55162.54.0.0/16162.54.0.1 to 162.54.255.254162.54.255.25565,534
56162.55.0.0/16162.55.0.1 to 162.55.255.254162.55.255.25565,534
57162.56.0.0/16162.56.0.1 to 162.56.255.254162.56.255.25565,534
58162.57.0.0/16162.57.0.1 to 162.57.255.254162.57.255.25565,534
59162.58.0.0/16162.58.0.1 to 162.58.255.254162.58.255.25565,534
60162.59.0.0/16162.59.0.1 to 162.59.255.254162.59.255.25565,534
61162.60.0.0/16162.60.0.1 to 162.60.255.254162.60.255.25565,534
62162.61.0.0/16162.61.0.1 to 162.61.255.254162.61.255.25565,534
63162.62.0.0/16162.62.0.1 to 162.62.255.254162.62.255.25565,534
64162.63.0.0/16162.63.0.1 to 162.63.255.254162.63.255.25565,534
65162.64.0.0/16162.64.0.1 to 162.64.255.254162.64.255.25565,534
66162.65.0.0/16162.65.0.1 to 162.65.255.254162.65.255.25565,534
67162.66.0.0/16162.66.0.1 to 162.66.255.254162.66.255.25565,534
68162.67.0.0/16162.67.0.1 to 162.67.255.254162.67.255.25565,534
69162.68.0.0/16162.68.0.1 to 162.68.255.254162.68.255.25565,534
70162.69.0.0/16162.69.0.1 to 162.69.255.254162.69.255.25565,534
71162.70.0.0/16162.70.0.1 to 162.70.255.254162.70.255.25565,534
72162.71.0.0/16162.71.0.1 to 162.71.255.254162.71.255.25565,534
73162.72.0.0/16162.72.0.1 to 162.72.255.254162.72.255.25565,534
74162.73.0.0/16162.73.0.1 to 162.73.255.254162.73.255.25565,534
75162.74.0.0/16162.74.0.1 to 162.74.255.254162.74.255.25565,534
76162.75.0.0/16162.75.0.1 to 162.75.255.254162.75.255.25565,534
77162.76.0.0/16162.76.0.1 to 162.76.255.254162.76.255.25565,534
78162.77.0.0/16162.77.0.1 to 162.77.255.254162.77.255.25565,534
79162.78.0.0/16162.78.0.1 to 162.78.255.254162.78.255.25565,534
80162.79.0.0/16162.79.0.1 to 162.79.255.254162.79.255.25565,534
81162.80.0.0/16162.80.0.1 to 162.80.255.254162.80.255.25565,534
82162.81.0.0/16162.81.0.1 to 162.81.255.254162.81.255.25565,534
83162.82.0.0/16162.82.0.1 to 162.82.255.254162.82.255.25565,534
84162.83.0.0/16162.83.0.1 to 162.83.255.254162.83.255.25565,534
85162.84.0.0/16162.84.0.1 to 162.84.255.254162.84.255.25565,534
86162.85.0.0/16162.85.0.1 to 162.85.255.254162.85.255.25565,534
87162.86.0.0/16162.86.0.1 to 162.86.255.254162.86.255.25565,534
88162.87.0.0/16162.87.0.1 to 162.87.255.254162.87.255.25565,534
89162.88.0.0/16162.88.0.1 to 162.88.255.254162.88.255.25565,534
90162.89.0.0/16162.89.0.1 to 162.89.255.254162.89.255.25565,534
91162.90.0.0/16162.90.0.1 to 162.90.255.254162.90.255.25565,534
92162.91.0.0/16162.91.0.1 to 162.91.255.254162.91.255.25565,534
93162.92.0.0/16162.92.0.1 to 162.92.255.254162.92.255.25565,534
94162.93.0.0/16162.93.0.1 to 162.93.255.254162.93.255.25565,534
95162.94.0.0/16162.94.0.1 to 162.94.255.254162.94.255.25565,534
96162.95.0.0/16162.95.0.1 to 162.95.255.254162.95.255.25565,534
97162.96.0.0/16162.96.0.1 to 162.96.255.254162.96.255.25565,534
98162.97.0.0/16162.97.0.1 to 162.97.255.254162.97.255.25565,534
99162.98.0.0/16162.98.0.1 to 162.98.255.254162.98.255.25565,534
100162.99.0.0/16162.99.0.1 to 162.99.255.254162.99.255.25565,534
101162.100.0.0/16162.100.0.1 to 162.100.255.254162.100.255.25565,534
102162.101.0.0/16162.101.0.1 to 162.101.255.254162.101.255.25565,534
103162.102.0.0/16162.102.0.1 to 162.102.255.254162.102.255.25565,534
104162.103.0.0/16162.103.0.1 to 162.103.255.254162.103.255.25565,534
105162.104.0.0/16162.104.0.1 to 162.104.255.254162.104.255.25565,534
106162.105.0.0/16162.105.0.1 to 162.105.255.254162.105.255.25565,534
107162.106.0.0/16162.106.0.1 to 162.106.255.254162.106.255.25565,534
108162.107.0.0/16162.107.0.1 to 162.107.255.254162.107.255.25565,534
109162.108.0.0/16162.108.0.1 to 162.108.255.254162.108.255.25565,534
110162.109.0.0/16162.109.0.1 to 162.109.255.254162.109.255.25565,534
111162.110.0.0/16162.110.0.1 to 162.110.255.254162.110.255.25565,534
112162.111.0.0/16162.111.0.1 to 162.111.255.254162.111.255.25565,534
113162.112.0.0/16162.112.0.1 to 162.112.255.254162.112.255.25565,534
114162.113.0.0/16162.113.0.1 to 162.113.255.254162.113.255.25565,534
115162.114.0.0/16162.114.0.1 to 162.114.255.254162.114.255.25565,534
116162.115.0.0/16162.115.0.1 to 162.115.255.254162.115.255.25565,534
117162.116.0.0/16162.116.0.1 to 162.116.255.254162.116.255.25565,534
118162.117.0.0/16162.117.0.1 to 162.117.255.254162.117.255.25565,534
119162.118.0.0/16162.118.0.1 to 162.118.255.254162.118.255.25565,534
120162.119.0.0/16162.119.0.1 to 162.119.255.254162.119.255.25565,534
121162.120.0.0/16162.120.0.1 to 162.120.255.254162.120.255.25565,534
122162.121.0.0/16162.121.0.1 to 162.121.255.254162.121.255.25565,534
123162.122.0.0/16162.122.0.1 to 162.122.255.254162.122.255.25565,534
124162.123.0.0/16162.123.0.1 to 162.123.255.254162.123.255.25565,534
125162.124.0.0/16162.124.0.1 to 162.124.255.254162.124.255.25565,534
126162.125.0.0/16162.125.0.1 to 162.125.255.254162.125.255.25565,534
127162.126.0.0/16162.126.0.1 to 162.126.255.254162.126.255.25565,534
128162.127.0.0/16162.127.0.1 to 162.127.255.254162.127.255.25565,534
129162.128.0.0/16162.128.0.1 to 162.128.255.254162.128.255.25565,534
130162.129.0.0/16162.129.0.1 to 162.129.255.254162.129.255.25565,534
131162.130.0.0/16162.130.0.1 to 162.130.255.254162.130.255.25565,534
132162.131.0.0/16162.131.0.1 to 162.131.255.254162.131.255.25565,534
133162.132.0.0/16162.132.0.1 to 162.132.255.254162.132.255.25565,534
134162.133.0.0/16162.133.0.1 to 162.133.255.254162.133.255.25565,534
135162.134.0.0/16162.134.0.1 to 162.134.255.254162.134.255.25565,534
136162.135.0.0/16162.135.0.1 to 162.135.255.254162.135.255.25565,534
137162.136.0.0/16162.136.0.1 to 162.136.255.254162.136.255.25565,534
138162.137.0.0/16162.137.0.1 to 162.137.255.254162.137.255.25565,534
139162.138.0.0/16162.138.0.1 to 162.138.255.254162.138.255.25565,534
140162.139.0.0/16162.139.0.1 to 162.139.255.254162.139.255.25565,534
141162.140.0.0/16162.140.0.1 to 162.140.255.254162.140.255.25565,534
142162.141.0.0/16162.141.0.1 to 162.141.255.254162.141.255.25565,534
143162.142.0.0/16162.142.0.1 to 162.142.255.254162.142.255.25565,534
144162.143.0.0/16162.143.0.1 to 162.143.255.254162.143.255.25565,534
145162.144.0.0/16162.144.0.1 to 162.144.255.254162.144.255.25565,534
146162.145.0.0/16162.145.0.1 to 162.145.255.254162.145.255.25565,534
147162.146.0.0/16162.146.0.1 to 162.146.255.254162.146.255.25565,534
148162.147.0.0/16162.147.0.1 to 162.147.255.254162.147.255.25565,534
149162.148.0.0/16162.148.0.1 to 162.148.255.254162.148.255.25565,534
150162.149.0.0/16162.149.0.1 to 162.149.255.254162.149.255.25565,534
151162.150.0.0/16162.150.0.1 to 162.150.255.254162.150.255.25565,534
152162.151.0.0/16162.151.0.1 to 162.151.255.254162.151.255.25565,534
153162.152.0.0/16162.152.0.1 to 162.152.255.254162.152.255.25565,534
154162.153.0.0/16162.153.0.1 to 162.153.255.254162.153.255.25565,534
155162.154.0.0/16162.154.0.1 to 162.154.255.254162.154.255.25565,534
156162.155.0.0/16162.155.0.1 to 162.155.255.254162.155.255.25565,534
157162.156.0.0/16162.156.0.1 to 162.156.255.254162.156.255.25565,534
158162.157.0.0/16162.157.0.1 to 162.157.255.254162.157.255.25565,534
159162.158.0.0/16162.158.0.1 to 162.158.255.254162.158.255.25565,534
160162.159.0.0/16162.159.0.1 to 162.159.255.254162.159.255.25565,534
161162.160.0.0/16162.160.0.1 to 162.160.255.254162.160.255.25565,534
162162.161.0.0/16162.161.0.1 to 162.161.255.254162.161.255.25565,534
163162.162.0.0/16162.162.0.1 to 162.162.255.254162.162.255.25565,534
164162.163.0.0/16162.163.0.1 to 162.163.255.254162.163.255.25565,534
165162.164.0.0/16162.164.0.1 to 162.164.255.254162.164.255.25565,534
166162.165.0.0/16162.165.0.1 to 162.165.255.254162.165.255.25565,534
167162.166.0.0/16162.166.0.1 to 162.166.255.254162.166.255.25565,534
168162.167.0.0/16162.167.0.1 to 162.167.255.254162.167.255.25565,534
169162.168.0.0/16162.168.0.1 to 162.168.255.254162.168.255.25565,534
170162.169.0.0/16162.169.0.1 to 162.169.255.254162.169.255.25565,534
171162.170.0.0/16162.170.0.1 to 162.170.255.254162.170.255.25565,534
172162.171.0.0/16162.171.0.1 to 162.171.255.254162.171.255.25565,534
173162.172.0.0/16162.172.0.1 to 162.172.255.254162.172.255.25565,534
174162.173.0.0/16162.173.0.1 to 162.173.255.254162.173.255.25565,534
175162.174.0.0/16162.174.0.1 to 162.174.255.254162.174.255.25565,534
176162.175.0.0/16162.175.0.1 to 162.175.255.254162.175.255.25565,534
177162.176.0.0/16162.176.0.1 to 162.176.255.254162.176.255.25565,534
178162.177.0.0/16162.177.0.1 to 162.177.255.254162.177.255.25565,534
179162.178.0.0/16162.178.0.1 to 162.178.255.254162.178.255.25565,534
180162.179.0.0/16162.179.0.1 to 162.179.255.254162.179.255.25565,534
181162.180.0.0/16162.180.0.1 to 162.180.255.254162.180.255.25565,534
182162.181.0.0/16162.181.0.1 to 162.181.255.254162.181.255.25565,534
183162.182.0.0/16162.182.0.1 to 162.182.255.254162.182.255.25565,534
184162.183.0.0/16162.183.0.1 to 162.183.255.254162.183.255.25565,534
185162.184.0.0/16162.184.0.1 to 162.184.255.254162.184.255.25565,534
186162.185.0.0/16162.185.0.1 to 162.185.255.254162.185.255.25565,534
187162.186.0.0/16162.186.0.1 to 162.186.255.254162.186.255.25565,534
188162.187.0.0/16162.187.0.1 to 162.187.255.254162.187.255.25565,534
189162.188.0.0/16162.188.0.1 to 162.188.255.254162.188.255.25565,534
190162.189.0.0/16162.189.0.1 to 162.189.255.254162.189.255.25565,534
191162.190.0.0/16162.190.0.1 to 162.190.255.254162.190.255.25565,534
192162.191.0.0/16162.191.0.1 to 162.191.255.254162.191.255.25565,534
193162.192.0.0/16162.192.0.1 to 162.192.255.254162.192.255.25565,534
194162.193.0.0/16162.193.0.1 to 162.193.255.254162.193.255.25565,534
195162.194.0.0/16162.194.0.1 to 162.194.255.254162.194.255.25565,534
196162.195.0.0/16162.195.0.1 to 162.195.255.254162.195.255.25565,534
197162.196.0.0/16162.196.0.1 to 162.196.255.254162.196.255.25565,534
198162.197.0.0/16162.197.0.1 to 162.197.255.254162.197.255.25565,534
199162.198.0.0/16162.198.0.1 to 162.198.255.254162.198.255.25565,534
200162.199.0.0/16162.199.0.1 to 162.199.255.254162.199.255.25565,534
201162.200.0.0/16162.200.0.1 to 162.200.255.254162.200.255.25565,534
202162.201.0.0/16162.201.0.1 to 162.201.255.254162.201.255.25565,534
203162.202.0.0/16162.202.0.1 to 162.202.255.254162.202.255.25565,534
204162.203.0.0/16162.203.0.1 to 162.203.255.254162.203.255.25565,534
205162.204.0.0/16162.204.0.1 to 162.204.255.254162.204.255.25565,534
206162.205.0.0/16162.205.0.1 to 162.205.255.254162.205.255.25565,534
207162.206.0.0/16162.206.0.1 to 162.206.255.254162.206.255.25565,534
208162.207.0.0/16162.207.0.1 to 162.207.255.254162.207.255.25565,534
209162.208.0.0/16162.208.0.1 to 162.208.255.254162.208.255.25565,534
210162.209.0.0/16162.209.0.1 to 162.209.255.254162.209.255.25565,534
211162.210.0.0/16162.210.0.1 to 162.210.255.254162.210.255.25565,534
212162.211.0.0/16162.211.0.1 to 162.211.255.254162.211.255.25565,534
213162.212.0.0/16162.212.0.1 to 162.212.255.254162.212.255.25565,534
214162.213.0.0/16162.213.0.1 to 162.213.255.254162.213.255.25565,534
215162.214.0.0/16162.214.0.1 to 162.214.255.254162.214.255.25565,534
216162.215.0.0/16162.215.0.1 to 162.215.255.254162.215.255.25565,534
217162.216.0.0/16162.216.0.1 to 162.216.255.254162.216.255.25565,534
218162.217.0.0/16162.217.0.1 to 162.217.255.254162.217.255.25565,534
219162.218.0.0/16162.218.0.1 to 162.218.255.254162.218.255.25565,534
220162.219.0.0/16162.219.0.1 to 162.219.255.254162.219.255.25565,534
221162.220.0.0/16162.220.0.1 to 162.220.255.254162.220.255.25565,534
222162.221.0.0/16162.221.0.1 to 162.221.255.254162.221.255.25565,534
223162.222.0.0/16162.222.0.1 to 162.222.255.254162.222.255.25565,534
224162.223.0.0/16162.223.0.1 to 162.223.255.254162.223.255.25565,534
225162.224.0.0/16162.224.0.1 to 162.224.255.254162.224.255.25565,534
226162.225.0.0/16162.225.0.1 to 162.225.255.254162.225.255.25565,534
227162.226.0.0/16162.226.0.1 to 162.226.255.254162.226.255.25565,534
228162.227.0.0/16162.227.0.1 to 162.227.255.254162.227.255.25565,534
229162.228.0.0/16162.228.0.1 to 162.228.255.254162.228.255.25565,534
230162.229.0.0/16162.229.0.1 to 162.229.255.254162.229.255.25565,534
231162.230.0.0/16162.230.0.1 to 162.230.255.254162.230.255.25565,534
232162.231.0.0/16162.231.0.1 to 162.231.255.254162.231.255.25565,534
233162.232.0.0/16162.232.0.1 to 162.232.255.254162.232.255.25565,534
234162.233.0.0/16162.233.0.1 to 162.233.255.254162.233.255.25565,534
235162.234.0.0/16162.234.0.1 to 162.234.255.254162.234.255.25565,534
236162.235.0.0/16162.235.0.1 to 162.235.255.254162.235.255.25565,534
237162.236.0.0/16162.236.0.1 to 162.236.255.254162.236.255.25565,534
238162.237.0.0/16162.237.0.1 to 162.237.255.254162.237.255.25565,534
239162.238.0.0/16162.238.0.1 to 162.238.255.254162.238.255.25565,534
240162.239.0.0/16162.239.0.1 to 162.239.255.254162.239.255.25565,534
241162.240.0.0/16162.240.0.1 to 162.240.255.254162.240.255.25565,534
242162.241.0.0/16162.241.0.1 to 162.241.255.254162.241.255.25565,534
243162.242.0.0/16162.242.0.1 to 162.242.255.254162.242.255.25565,534
244162.243.0.0/16162.243.0.1 to 162.243.255.254162.243.255.25565,534
245162.244.0.0/16162.244.0.1 to 162.244.255.254162.244.255.25565,534
246162.245.0.0/16162.245.0.1 to 162.245.255.254162.245.255.25565,534
247162.246.0.0/16162.246.0.1 to 162.246.255.254162.246.255.25565,534
248162.247.0.0/16162.247.0.1 to 162.247.255.254162.247.255.25565,534
249162.248.0.0/16162.248.0.1 to 162.248.255.254162.248.255.25565,534
250162.249.0.0/16162.249.0.1 to 162.249.255.254162.249.255.25565,534
251162.250.0.0/16162.250.0.1 to 162.250.255.254162.250.255.25565,534
252162.251.0.0/16162.251.0.1 to 162.251.255.254162.251.255.25565,534
253162.252.0.0/16162.252.0.1 to 162.252.255.254162.252.255.25565,534
254162.253.0.0/16162.253.0.1 to 162.253.255.254162.253.255.25565,534
255162.254.0.0/16162.254.0.1 to 162.254.255.254162.254.255.25565,534
256162.255.0.0/16162.255.0.1 to 162.255.255.254162.255.255.25565,534

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.