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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.

Network162.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
162.0.0.0
Broadcast address
163.255.255.255
First usable
162.0.0.1
Last usable
163.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
B (default /16)
As numbers
Hex A2000000 · Integer 2717908992 to 2751463423
Reverse DNS zones
162.in-addr.arpa
163.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10100010.00000000.00000000.00000000162.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10100010.00000000.00000000.00000000162.0.0.0
Broadcast10100011.11111111.11111111.11111111163.255.255.255
Split into smaller subnets/15
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

162.0.0.0/7 makes 256 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1162.0.0.0/15162.0.0.1 to 162.1.255.254162.1.255.255131,070
2162.2.0.0/15162.2.0.1 to 162.3.255.254162.3.255.255131,070
3162.4.0.0/15162.4.0.1 to 162.5.255.254162.5.255.255131,070
4162.6.0.0/15162.6.0.1 to 162.7.255.254162.7.255.255131,070
5162.8.0.0/15162.8.0.1 to 162.9.255.254162.9.255.255131,070
6162.10.0.0/15162.10.0.1 to 162.11.255.254162.11.255.255131,070
7162.12.0.0/15162.12.0.1 to 162.13.255.254162.13.255.255131,070
8162.14.0.0/15162.14.0.1 to 162.15.255.254162.15.255.255131,070
9162.16.0.0/15162.16.0.1 to 162.17.255.254162.17.255.255131,070
10162.18.0.0/15162.18.0.1 to 162.19.255.254162.19.255.255131,070
11162.20.0.0/15162.20.0.1 to 162.21.255.254162.21.255.255131,070
12162.22.0.0/15162.22.0.1 to 162.23.255.254162.23.255.255131,070
13162.24.0.0/15162.24.0.1 to 162.25.255.254162.25.255.255131,070
14162.26.0.0/15162.26.0.1 to 162.27.255.254162.27.255.255131,070
15162.28.0.0/15162.28.0.1 to 162.29.255.254162.29.255.255131,070
16162.30.0.0/15162.30.0.1 to 162.31.255.254162.31.255.255131,070
17162.32.0.0/15162.32.0.1 to 162.33.255.254162.33.255.255131,070
18162.34.0.0/15162.34.0.1 to 162.35.255.254162.35.255.255131,070
19162.36.0.0/15162.36.0.1 to 162.37.255.254162.37.255.255131,070
20162.38.0.0/15162.38.0.1 to 162.39.255.254162.39.255.255131,070
21162.40.0.0/15162.40.0.1 to 162.41.255.254162.41.255.255131,070
22162.42.0.0/15162.42.0.1 to 162.43.255.254162.43.255.255131,070
23162.44.0.0/15162.44.0.1 to 162.45.255.254162.45.255.255131,070
24162.46.0.0/15162.46.0.1 to 162.47.255.254162.47.255.255131,070
25162.48.0.0/15162.48.0.1 to 162.49.255.254162.49.255.255131,070
26162.50.0.0/15162.50.0.1 to 162.51.255.254162.51.255.255131,070
27162.52.0.0/15162.52.0.1 to 162.53.255.254162.53.255.255131,070
28162.54.0.0/15162.54.0.1 to 162.55.255.254162.55.255.255131,070
29162.56.0.0/15162.56.0.1 to 162.57.255.254162.57.255.255131,070
30162.58.0.0/15162.58.0.1 to 162.59.255.254162.59.255.255131,070
31162.60.0.0/15162.60.0.1 to 162.61.255.254162.61.255.255131,070
32162.62.0.0/15162.62.0.1 to 162.63.255.254162.63.255.255131,070
33162.64.0.0/15162.64.0.1 to 162.65.255.254162.65.255.255131,070
34162.66.0.0/15162.66.0.1 to 162.67.255.254162.67.255.255131,070
35162.68.0.0/15162.68.0.1 to 162.69.255.254162.69.255.255131,070
36162.70.0.0/15162.70.0.1 to 162.71.255.254162.71.255.255131,070
37162.72.0.0/15162.72.0.1 to 162.73.255.254162.73.255.255131,070
38162.74.0.0/15162.74.0.1 to 162.75.255.254162.75.255.255131,070
39162.76.0.0/15162.76.0.1 to 162.77.255.254162.77.255.255131,070
40162.78.0.0/15162.78.0.1 to 162.79.255.254162.79.255.255131,070
41162.80.0.0/15162.80.0.1 to 162.81.255.254162.81.255.255131,070
42162.82.0.0/15162.82.0.1 to 162.83.255.254162.83.255.255131,070
43162.84.0.0/15162.84.0.1 to 162.85.255.254162.85.255.255131,070
44162.86.0.0/15162.86.0.1 to 162.87.255.254162.87.255.255131,070
45162.88.0.0/15162.88.0.1 to 162.89.255.254162.89.255.255131,070
46162.90.0.0/15162.90.0.1 to 162.91.255.254162.91.255.255131,070
47162.92.0.0/15162.92.0.1 to 162.93.255.254162.93.255.255131,070
48162.94.0.0/15162.94.0.1 to 162.95.255.254162.95.255.255131,070
49162.96.0.0/15162.96.0.1 to 162.97.255.254162.97.255.255131,070
50162.98.0.0/15162.98.0.1 to 162.99.255.254162.99.255.255131,070
51162.100.0.0/15162.100.0.1 to 162.101.255.254162.101.255.255131,070
52162.102.0.0/15162.102.0.1 to 162.103.255.254162.103.255.255131,070
53162.104.0.0/15162.104.0.1 to 162.105.255.254162.105.255.255131,070
54162.106.0.0/15162.106.0.1 to 162.107.255.254162.107.255.255131,070
55162.108.0.0/15162.108.0.1 to 162.109.255.254162.109.255.255131,070
56162.110.0.0/15162.110.0.1 to 162.111.255.254162.111.255.255131,070
57162.112.0.0/15162.112.0.1 to 162.113.255.254162.113.255.255131,070
58162.114.0.0/15162.114.0.1 to 162.115.255.254162.115.255.255131,070
59162.116.0.0/15162.116.0.1 to 162.117.255.254162.117.255.255131,070
60162.118.0.0/15162.118.0.1 to 162.119.255.254162.119.255.255131,070
61162.120.0.0/15162.120.0.1 to 162.121.255.254162.121.255.255131,070
62162.122.0.0/15162.122.0.1 to 162.123.255.254162.123.255.255131,070
63162.124.0.0/15162.124.0.1 to 162.125.255.254162.125.255.255131,070
64162.126.0.0/15162.126.0.1 to 162.127.255.254162.127.255.255131,070
65162.128.0.0/15162.128.0.1 to 162.129.255.254162.129.255.255131,070
66162.130.0.0/15162.130.0.1 to 162.131.255.254162.131.255.255131,070
67162.132.0.0/15162.132.0.1 to 162.133.255.254162.133.255.255131,070
68162.134.0.0/15162.134.0.1 to 162.135.255.254162.135.255.255131,070
69162.136.0.0/15162.136.0.1 to 162.137.255.254162.137.255.255131,070
70162.138.0.0/15162.138.0.1 to 162.139.255.254162.139.255.255131,070
71162.140.0.0/15162.140.0.1 to 162.141.255.254162.141.255.255131,070
72162.142.0.0/15162.142.0.1 to 162.143.255.254162.143.255.255131,070
73162.144.0.0/15162.144.0.1 to 162.145.255.254162.145.255.255131,070
74162.146.0.0/15162.146.0.1 to 162.147.255.254162.147.255.255131,070
75162.148.0.0/15162.148.0.1 to 162.149.255.254162.149.255.255131,070
76162.150.0.0/15162.150.0.1 to 162.151.255.254162.151.255.255131,070
77162.152.0.0/15162.152.0.1 to 162.153.255.254162.153.255.255131,070
78162.154.0.0/15162.154.0.1 to 162.155.255.254162.155.255.255131,070
79162.156.0.0/15162.156.0.1 to 162.157.255.254162.157.255.255131,070
80162.158.0.0/15162.158.0.1 to 162.159.255.254162.159.255.255131,070
81162.160.0.0/15162.160.0.1 to 162.161.255.254162.161.255.255131,070
82162.162.0.0/15162.162.0.1 to 162.163.255.254162.163.255.255131,070
83162.164.0.0/15162.164.0.1 to 162.165.255.254162.165.255.255131,070
84162.166.0.0/15162.166.0.1 to 162.167.255.254162.167.255.255131,070
85162.168.0.0/15162.168.0.1 to 162.169.255.254162.169.255.255131,070
86162.170.0.0/15162.170.0.1 to 162.171.255.254162.171.255.255131,070
87162.172.0.0/15162.172.0.1 to 162.173.255.254162.173.255.255131,070
88162.174.0.0/15162.174.0.1 to 162.175.255.254162.175.255.255131,070
89162.176.0.0/15162.176.0.1 to 162.177.255.254162.177.255.255131,070
90162.178.0.0/15162.178.0.1 to 162.179.255.254162.179.255.255131,070
91162.180.0.0/15162.180.0.1 to 162.181.255.254162.181.255.255131,070
92162.182.0.0/15162.182.0.1 to 162.183.255.254162.183.255.255131,070
93162.184.0.0/15162.184.0.1 to 162.185.255.254162.185.255.255131,070
94162.186.0.0/15162.186.0.1 to 162.187.255.254162.187.255.255131,070
95162.188.0.0/15162.188.0.1 to 162.189.255.254162.189.255.255131,070
96162.190.0.0/15162.190.0.1 to 162.191.255.254162.191.255.255131,070
97162.192.0.0/15162.192.0.1 to 162.193.255.254162.193.255.255131,070
98162.194.0.0/15162.194.0.1 to 162.195.255.254162.195.255.255131,070
99162.196.0.0/15162.196.0.1 to 162.197.255.254162.197.255.255131,070
100162.198.0.0/15162.198.0.1 to 162.199.255.254162.199.255.255131,070
101162.200.0.0/15162.200.0.1 to 162.201.255.254162.201.255.255131,070
102162.202.0.0/15162.202.0.1 to 162.203.255.254162.203.255.255131,070
103162.204.0.0/15162.204.0.1 to 162.205.255.254162.205.255.255131,070
104162.206.0.0/15162.206.0.1 to 162.207.255.254162.207.255.255131,070
105162.208.0.0/15162.208.0.1 to 162.209.255.254162.209.255.255131,070
106162.210.0.0/15162.210.0.1 to 162.211.255.254162.211.255.255131,070
107162.212.0.0/15162.212.0.1 to 162.213.255.254162.213.255.255131,070
108162.214.0.0/15162.214.0.1 to 162.215.255.254162.215.255.255131,070
109162.216.0.0/15162.216.0.1 to 162.217.255.254162.217.255.255131,070
110162.218.0.0/15162.218.0.1 to 162.219.255.254162.219.255.255131,070
111162.220.0.0/15162.220.0.1 to 162.221.255.254162.221.255.255131,070
112162.222.0.0/15162.222.0.1 to 162.223.255.254162.223.255.255131,070
113162.224.0.0/15162.224.0.1 to 162.225.255.254162.225.255.255131,070
114162.226.0.0/15162.226.0.1 to 162.227.255.254162.227.255.255131,070
115162.228.0.0/15162.228.0.1 to 162.229.255.254162.229.255.255131,070
116162.230.0.0/15162.230.0.1 to 162.231.255.254162.231.255.255131,070
117162.232.0.0/15162.232.0.1 to 162.233.255.254162.233.255.255131,070
118162.234.0.0/15162.234.0.1 to 162.235.255.254162.235.255.255131,070
119162.236.0.0/15162.236.0.1 to 162.237.255.254162.237.255.255131,070
120162.238.0.0/15162.238.0.1 to 162.239.255.254162.239.255.255131,070
121162.240.0.0/15162.240.0.1 to 162.241.255.254162.241.255.255131,070
122162.242.0.0/15162.242.0.1 to 162.243.255.254162.243.255.255131,070
123162.244.0.0/15162.244.0.1 to 162.245.255.254162.245.255.255131,070
124162.246.0.0/15162.246.0.1 to 162.247.255.254162.247.255.255131,070
125162.248.0.0/15162.248.0.1 to 162.249.255.254162.249.255.255131,070
126162.250.0.0/15162.250.0.1 to 162.251.255.254162.251.255.255131,070
127162.252.0.0/15162.252.0.1 to 162.253.255.254162.253.255.255131,070
128162.254.0.0/15162.254.0.1 to 162.255.255.254162.255.255.255131,070
129163.0.0.0/15163.0.0.1 to 163.1.255.254163.1.255.255131,070
130163.2.0.0/15163.2.0.1 to 163.3.255.254163.3.255.255131,070
131163.4.0.0/15163.4.0.1 to 163.5.255.254163.5.255.255131,070
132163.6.0.0/15163.6.0.1 to 163.7.255.254163.7.255.255131,070
133163.8.0.0/15163.8.0.1 to 163.9.255.254163.9.255.255131,070
134163.10.0.0/15163.10.0.1 to 163.11.255.254163.11.255.255131,070
135163.12.0.0/15163.12.0.1 to 163.13.255.254163.13.255.255131,070
136163.14.0.0/15163.14.0.1 to 163.15.255.254163.15.255.255131,070
137163.16.0.0/15163.16.0.1 to 163.17.255.254163.17.255.255131,070
138163.18.0.0/15163.18.0.1 to 163.19.255.254163.19.255.255131,070
139163.20.0.0/15163.20.0.1 to 163.21.255.254163.21.255.255131,070
140163.22.0.0/15163.22.0.1 to 163.23.255.254163.23.255.255131,070
141163.24.0.0/15163.24.0.1 to 163.25.255.254163.25.255.255131,070
142163.26.0.0/15163.26.0.1 to 163.27.255.254163.27.255.255131,070
143163.28.0.0/15163.28.0.1 to 163.29.255.254163.29.255.255131,070
144163.30.0.0/15163.30.0.1 to 163.31.255.254163.31.255.255131,070
145163.32.0.0/15163.32.0.1 to 163.33.255.254163.33.255.255131,070
146163.34.0.0/15163.34.0.1 to 163.35.255.254163.35.255.255131,070
147163.36.0.0/15163.36.0.1 to 163.37.255.254163.37.255.255131,070
148163.38.0.0/15163.38.0.1 to 163.39.255.254163.39.255.255131,070
149163.40.0.0/15163.40.0.1 to 163.41.255.254163.41.255.255131,070
150163.42.0.0/15163.42.0.1 to 163.43.255.254163.43.255.255131,070
151163.44.0.0/15163.44.0.1 to 163.45.255.254163.45.255.255131,070
152163.46.0.0/15163.46.0.1 to 163.47.255.254163.47.255.255131,070
153163.48.0.0/15163.48.0.1 to 163.49.255.254163.49.255.255131,070
154163.50.0.0/15163.50.0.1 to 163.51.255.254163.51.255.255131,070
155163.52.0.0/15163.52.0.1 to 163.53.255.254163.53.255.255131,070
156163.54.0.0/15163.54.0.1 to 163.55.255.254163.55.255.255131,070
157163.56.0.0/15163.56.0.1 to 163.57.255.254163.57.255.255131,070
158163.58.0.0/15163.58.0.1 to 163.59.255.254163.59.255.255131,070
159163.60.0.0/15163.60.0.1 to 163.61.255.254163.61.255.255131,070
160163.62.0.0/15163.62.0.1 to 163.63.255.254163.63.255.255131,070
161163.64.0.0/15163.64.0.1 to 163.65.255.254163.65.255.255131,070
162163.66.0.0/15163.66.0.1 to 163.67.255.254163.67.255.255131,070
163163.68.0.0/15163.68.0.1 to 163.69.255.254163.69.255.255131,070
164163.70.0.0/15163.70.0.1 to 163.71.255.254163.71.255.255131,070
165163.72.0.0/15163.72.0.1 to 163.73.255.254163.73.255.255131,070
166163.74.0.0/15163.74.0.1 to 163.75.255.254163.75.255.255131,070
167163.76.0.0/15163.76.0.1 to 163.77.255.254163.77.255.255131,070
168163.78.0.0/15163.78.0.1 to 163.79.255.254163.79.255.255131,070
169163.80.0.0/15163.80.0.1 to 163.81.255.254163.81.255.255131,070
170163.82.0.0/15163.82.0.1 to 163.83.255.254163.83.255.255131,070
171163.84.0.0/15163.84.0.1 to 163.85.255.254163.85.255.255131,070
172163.86.0.0/15163.86.0.1 to 163.87.255.254163.87.255.255131,070
173163.88.0.0/15163.88.0.1 to 163.89.255.254163.89.255.255131,070
174163.90.0.0/15163.90.0.1 to 163.91.255.254163.91.255.255131,070
175163.92.0.0/15163.92.0.1 to 163.93.255.254163.93.255.255131,070
176163.94.0.0/15163.94.0.1 to 163.95.255.254163.95.255.255131,070
177163.96.0.0/15163.96.0.1 to 163.97.255.254163.97.255.255131,070
178163.98.0.0/15163.98.0.1 to 163.99.255.254163.99.255.255131,070
179163.100.0.0/15163.100.0.1 to 163.101.255.254163.101.255.255131,070
180163.102.0.0/15163.102.0.1 to 163.103.255.254163.103.255.255131,070
181163.104.0.0/15163.104.0.1 to 163.105.255.254163.105.255.255131,070
182163.106.0.0/15163.106.0.1 to 163.107.255.254163.107.255.255131,070
183163.108.0.0/15163.108.0.1 to 163.109.255.254163.109.255.255131,070
184163.110.0.0/15163.110.0.1 to 163.111.255.254163.111.255.255131,070
185163.112.0.0/15163.112.0.1 to 163.113.255.254163.113.255.255131,070
186163.114.0.0/15163.114.0.1 to 163.115.255.254163.115.255.255131,070
187163.116.0.0/15163.116.0.1 to 163.117.255.254163.117.255.255131,070
188163.118.0.0/15163.118.0.1 to 163.119.255.254163.119.255.255131,070
189163.120.0.0/15163.120.0.1 to 163.121.255.254163.121.255.255131,070
190163.122.0.0/15163.122.0.1 to 163.123.255.254163.123.255.255131,070
191163.124.0.0/15163.124.0.1 to 163.125.255.254163.125.255.255131,070
192163.126.0.0/15163.126.0.1 to 163.127.255.254163.127.255.255131,070
193163.128.0.0/15163.128.0.1 to 163.129.255.254163.129.255.255131,070
194163.130.0.0/15163.130.0.1 to 163.131.255.254163.131.255.255131,070
195163.132.0.0/15163.132.0.1 to 163.133.255.254163.133.255.255131,070
196163.134.0.0/15163.134.0.1 to 163.135.255.254163.135.255.255131,070
197163.136.0.0/15163.136.0.1 to 163.137.255.254163.137.255.255131,070
198163.138.0.0/15163.138.0.1 to 163.139.255.254163.139.255.255131,070
199163.140.0.0/15163.140.0.1 to 163.141.255.254163.141.255.255131,070
200163.142.0.0/15163.142.0.1 to 163.143.255.254163.143.255.255131,070
201163.144.0.0/15163.144.0.1 to 163.145.255.254163.145.255.255131,070
202163.146.0.0/15163.146.0.1 to 163.147.255.254163.147.255.255131,070
203163.148.0.0/15163.148.0.1 to 163.149.255.254163.149.255.255131,070
204163.150.0.0/15163.150.0.1 to 163.151.255.254163.151.255.255131,070
205163.152.0.0/15163.152.0.1 to 163.153.255.254163.153.255.255131,070
206163.154.0.0/15163.154.0.1 to 163.155.255.254163.155.255.255131,070
207163.156.0.0/15163.156.0.1 to 163.157.255.254163.157.255.255131,070
208163.158.0.0/15163.158.0.1 to 163.159.255.254163.159.255.255131,070
209163.160.0.0/15163.160.0.1 to 163.161.255.254163.161.255.255131,070
210163.162.0.0/15163.162.0.1 to 163.163.255.254163.163.255.255131,070
211163.164.0.0/15163.164.0.1 to 163.165.255.254163.165.255.255131,070
212163.166.0.0/15163.166.0.1 to 163.167.255.254163.167.255.255131,070
213163.168.0.0/15163.168.0.1 to 163.169.255.254163.169.255.255131,070
214163.170.0.0/15163.170.0.1 to 163.171.255.254163.171.255.255131,070
215163.172.0.0/15163.172.0.1 to 163.173.255.254163.173.255.255131,070
216163.174.0.0/15163.174.0.1 to 163.175.255.254163.175.255.255131,070
217163.176.0.0/15163.176.0.1 to 163.177.255.254163.177.255.255131,070
218163.178.0.0/15163.178.0.1 to 163.179.255.254163.179.255.255131,070
219163.180.0.0/15163.180.0.1 to 163.181.255.254163.181.255.255131,070
220163.182.0.0/15163.182.0.1 to 163.183.255.254163.183.255.255131,070
221163.184.0.0/15163.184.0.1 to 163.185.255.254163.185.255.255131,070
222163.186.0.0/15163.186.0.1 to 163.187.255.254163.187.255.255131,070
223163.188.0.0/15163.188.0.1 to 163.189.255.254163.189.255.255131,070
224163.190.0.0/15163.190.0.1 to 163.191.255.254163.191.255.255131,070
225163.192.0.0/15163.192.0.1 to 163.193.255.254163.193.255.255131,070
226163.194.0.0/15163.194.0.1 to 163.195.255.254163.195.255.255131,070
227163.196.0.0/15163.196.0.1 to 163.197.255.254163.197.255.255131,070
228163.198.0.0/15163.198.0.1 to 163.199.255.254163.199.255.255131,070
229163.200.0.0/15163.200.0.1 to 163.201.255.254163.201.255.255131,070
230163.202.0.0/15163.202.0.1 to 163.203.255.254163.203.255.255131,070
231163.204.0.0/15163.204.0.1 to 163.205.255.254163.205.255.255131,070
232163.206.0.0/15163.206.0.1 to 163.207.255.254163.207.255.255131,070
233163.208.0.0/15163.208.0.1 to 163.209.255.254163.209.255.255131,070
234163.210.0.0/15163.210.0.1 to 163.211.255.254163.211.255.255131,070
235163.212.0.0/15163.212.0.1 to 163.213.255.254163.213.255.255131,070
236163.214.0.0/15163.214.0.1 to 163.215.255.254163.215.255.255131,070
237163.216.0.0/15163.216.0.1 to 163.217.255.254163.217.255.255131,070
238163.218.0.0/15163.218.0.1 to 163.219.255.254163.219.255.255131,070
239163.220.0.0/15163.220.0.1 to 163.221.255.254163.221.255.255131,070
240163.222.0.0/15163.222.0.1 to 163.223.255.254163.223.255.255131,070
241163.224.0.0/15163.224.0.1 to 163.225.255.254163.225.255.255131,070
242163.226.0.0/15163.226.0.1 to 163.227.255.254163.227.255.255131,070
243163.228.0.0/15163.228.0.1 to 163.229.255.254163.229.255.255131,070
244163.230.0.0/15163.230.0.1 to 163.231.255.254163.231.255.255131,070
245163.232.0.0/15163.232.0.1 to 163.233.255.254163.233.255.255131,070
246163.234.0.0/15163.234.0.1 to 163.235.255.254163.235.255.255131,070
247163.236.0.0/15163.236.0.1 to 163.237.255.254163.237.255.255131,070
248163.238.0.0/15163.238.0.1 to 163.239.255.254163.239.255.255131,070
249163.240.0.0/15163.240.0.1 to 163.241.255.254163.241.255.255131,070
250163.242.0.0/15163.242.0.1 to 163.243.255.254163.243.255.255131,070
251163.244.0.0/15163.244.0.1 to 163.245.255.254163.245.255.255131,070
252163.246.0.0/15163.246.0.1 to 163.247.255.254163.247.255.255131,070
253163.248.0.0/15163.248.0.1 to 163.249.255.254163.249.255.255131,070
254163.250.0.0/15163.250.0.1 to 163.251.255.254163.251.255.255131,070
255163.252.0.0/15163.252.0.1 to 163.253.255.254163.253.255.255131,070
256163.254.0.0/15163.254.0.1 to 163.255.255.254163.255.255.255131,070

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.