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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.

Network150.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
150.0.0.0
Broadcast address
151.255.255.255
First usable
150.0.0.1
Last usable
151.255.255.254
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 96000000 · Integer 2516582400 to 2550136831
Reverse DNS zones
150.in-addr.arpa
151.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
Address10010110.00000000.00000000.00000000150.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10010110.00000000.00000000.00000000150.0.0.0
Broadcast10010111.11111111.11111111.11111111151.255.255.255
Split into smaller subnets/16
/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)

150.0.0.0/7 makes 512 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1150.0.0.0/16150.0.0.1 to 150.0.255.254150.0.255.25565,534
2150.1.0.0/16150.1.0.1 to 150.1.255.254150.1.255.25565,534
3150.2.0.0/16150.2.0.1 to 150.2.255.254150.2.255.25565,534
4150.3.0.0/16150.3.0.1 to 150.3.255.254150.3.255.25565,534
5150.4.0.0/16150.4.0.1 to 150.4.255.254150.4.255.25565,534
6150.5.0.0/16150.5.0.1 to 150.5.255.254150.5.255.25565,534
7150.6.0.0/16150.6.0.1 to 150.6.255.254150.6.255.25565,534
8150.7.0.0/16150.7.0.1 to 150.7.255.254150.7.255.25565,534
9150.8.0.0/16150.8.0.1 to 150.8.255.254150.8.255.25565,534
10150.9.0.0/16150.9.0.1 to 150.9.255.254150.9.255.25565,534
11150.10.0.0/16150.10.0.1 to 150.10.255.254150.10.255.25565,534
12150.11.0.0/16150.11.0.1 to 150.11.255.254150.11.255.25565,534
13150.12.0.0/16150.12.0.1 to 150.12.255.254150.12.255.25565,534
14150.13.0.0/16150.13.0.1 to 150.13.255.254150.13.255.25565,534
15150.14.0.0/16150.14.0.1 to 150.14.255.254150.14.255.25565,534
16150.15.0.0/16150.15.0.1 to 150.15.255.254150.15.255.25565,534
17150.16.0.0/16150.16.0.1 to 150.16.255.254150.16.255.25565,534
18150.17.0.0/16150.17.0.1 to 150.17.255.254150.17.255.25565,534
19150.18.0.0/16150.18.0.1 to 150.18.255.254150.18.255.25565,534
20150.19.0.0/16150.19.0.1 to 150.19.255.254150.19.255.25565,534
21150.20.0.0/16150.20.0.1 to 150.20.255.254150.20.255.25565,534
22150.21.0.0/16150.21.0.1 to 150.21.255.254150.21.255.25565,534
23150.22.0.0/16150.22.0.1 to 150.22.255.254150.22.255.25565,534
24150.23.0.0/16150.23.0.1 to 150.23.255.254150.23.255.25565,534
25150.24.0.0/16150.24.0.1 to 150.24.255.254150.24.255.25565,534
26150.25.0.0/16150.25.0.1 to 150.25.255.254150.25.255.25565,534
27150.26.0.0/16150.26.0.1 to 150.26.255.254150.26.255.25565,534
28150.27.0.0/16150.27.0.1 to 150.27.255.254150.27.255.25565,534
29150.28.0.0/16150.28.0.1 to 150.28.255.254150.28.255.25565,534
30150.29.0.0/16150.29.0.1 to 150.29.255.254150.29.255.25565,534
31150.30.0.0/16150.30.0.1 to 150.30.255.254150.30.255.25565,534
32150.31.0.0/16150.31.0.1 to 150.31.255.254150.31.255.25565,534
33150.32.0.0/16150.32.0.1 to 150.32.255.254150.32.255.25565,534
34150.33.0.0/16150.33.0.1 to 150.33.255.254150.33.255.25565,534
35150.34.0.0/16150.34.0.1 to 150.34.255.254150.34.255.25565,534
36150.35.0.0/16150.35.0.1 to 150.35.255.254150.35.255.25565,534
37150.36.0.0/16150.36.0.1 to 150.36.255.254150.36.255.25565,534
38150.37.0.0/16150.37.0.1 to 150.37.255.254150.37.255.25565,534
39150.38.0.0/16150.38.0.1 to 150.38.255.254150.38.255.25565,534
40150.39.0.0/16150.39.0.1 to 150.39.255.254150.39.255.25565,534
41150.40.0.0/16150.40.0.1 to 150.40.255.254150.40.255.25565,534
42150.41.0.0/16150.41.0.1 to 150.41.255.254150.41.255.25565,534
43150.42.0.0/16150.42.0.1 to 150.42.255.254150.42.255.25565,534
44150.43.0.0/16150.43.0.1 to 150.43.255.254150.43.255.25565,534
45150.44.0.0/16150.44.0.1 to 150.44.255.254150.44.255.25565,534
46150.45.0.0/16150.45.0.1 to 150.45.255.254150.45.255.25565,534
47150.46.0.0/16150.46.0.1 to 150.46.255.254150.46.255.25565,534
48150.47.0.0/16150.47.0.1 to 150.47.255.254150.47.255.25565,534
49150.48.0.0/16150.48.0.1 to 150.48.255.254150.48.255.25565,534
50150.49.0.0/16150.49.0.1 to 150.49.255.254150.49.255.25565,534
51150.50.0.0/16150.50.0.1 to 150.50.255.254150.50.255.25565,534
52150.51.0.0/16150.51.0.1 to 150.51.255.254150.51.255.25565,534
53150.52.0.0/16150.52.0.1 to 150.52.255.254150.52.255.25565,534
54150.53.0.0/16150.53.0.1 to 150.53.255.254150.53.255.25565,534
55150.54.0.0/16150.54.0.1 to 150.54.255.254150.54.255.25565,534
56150.55.0.0/16150.55.0.1 to 150.55.255.254150.55.255.25565,534
57150.56.0.0/16150.56.0.1 to 150.56.255.254150.56.255.25565,534
58150.57.0.0/16150.57.0.1 to 150.57.255.254150.57.255.25565,534
59150.58.0.0/16150.58.0.1 to 150.58.255.254150.58.255.25565,534
60150.59.0.0/16150.59.0.1 to 150.59.255.254150.59.255.25565,534
61150.60.0.0/16150.60.0.1 to 150.60.255.254150.60.255.25565,534
62150.61.0.0/16150.61.0.1 to 150.61.255.254150.61.255.25565,534
63150.62.0.0/16150.62.0.1 to 150.62.255.254150.62.255.25565,534
64150.63.0.0/16150.63.0.1 to 150.63.255.254150.63.255.25565,534
65150.64.0.0/16150.64.0.1 to 150.64.255.254150.64.255.25565,534
66150.65.0.0/16150.65.0.1 to 150.65.255.254150.65.255.25565,534
67150.66.0.0/16150.66.0.1 to 150.66.255.254150.66.255.25565,534
68150.67.0.0/16150.67.0.1 to 150.67.255.254150.67.255.25565,534
69150.68.0.0/16150.68.0.1 to 150.68.255.254150.68.255.25565,534
70150.69.0.0/16150.69.0.1 to 150.69.255.254150.69.255.25565,534
71150.70.0.0/16150.70.0.1 to 150.70.255.254150.70.255.25565,534
72150.71.0.0/16150.71.0.1 to 150.71.255.254150.71.255.25565,534
73150.72.0.0/16150.72.0.1 to 150.72.255.254150.72.255.25565,534
74150.73.0.0/16150.73.0.1 to 150.73.255.254150.73.255.25565,534
75150.74.0.0/16150.74.0.1 to 150.74.255.254150.74.255.25565,534
76150.75.0.0/16150.75.0.1 to 150.75.255.254150.75.255.25565,534
77150.76.0.0/16150.76.0.1 to 150.76.255.254150.76.255.25565,534
78150.77.0.0/16150.77.0.1 to 150.77.255.254150.77.255.25565,534
79150.78.0.0/16150.78.0.1 to 150.78.255.254150.78.255.25565,534
80150.79.0.0/16150.79.0.1 to 150.79.255.254150.79.255.25565,534
81150.80.0.0/16150.80.0.1 to 150.80.255.254150.80.255.25565,534
82150.81.0.0/16150.81.0.1 to 150.81.255.254150.81.255.25565,534
83150.82.0.0/16150.82.0.1 to 150.82.255.254150.82.255.25565,534
84150.83.0.0/16150.83.0.1 to 150.83.255.254150.83.255.25565,534
85150.84.0.0/16150.84.0.1 to 150.84.255.254150.84.255.25565,534
86150.85.0.0/16150.85.0.1 to 150.85.255.254150.85.255.25565,534
87150.86.0.0/16150.86.0.1 to 150.86.255.254150.86.255.25565,534
88150.87.0.0/16150.87.0.1 to 150.87.255.254150.87.255.25565,534
89150.88.0.0/16150.88.0.1 to 150.88.255.254150.88.255.25565,534
90150.89.0.0/16150.89.0.1 to 150.89.255.254150.89.255.25565,534
91150.90.0.0/16150.90.0.1 to 150.90.255.254150.90.255.25565,534
92150.91.0.0/16150.91.0.1 to 150.91.255.254150.91.255.25565,534
93150.92.0.0/16150.92.0.1 to 150.92.255.254150.92.255.25565,534
94150.93.0.0/16150.93.0.1 to 150.93.255.254150.93.255.25565,534
95150.94.0.0/16150.94.0.1 to 150.94.255.254150.94.255.25565,534
96150.95.0.0/16150.95.0.1 to 150.95.255.254150.95.255.25565,534
97150.96.0.0/16150.96.0.1 to 150.96.255.254150.96.255.25565,534
98150.97.0.0/16150.97.0.1 to 150.97.255.254150.97.255.25565,534
99150.98.0.0/16150.98.0.1 to 150.98.255.254150.98.255.25565,534
100150.99.0.0/16150.99.0.1 to 150.99.255.254150.99.255.25565,534
101150.100.0.0/16150.100.0.1 to 150.100.255.254150.100.255.25565,534
102150.101.0.0/16150.101.0.1 to 150.101.255.254150.101.255.25565,534
103150.102.0.0/16150.102.0.1 to 150.102.255.254150.102.255.25565,534
104150.103.0.0/16150.103.0.1 to 150.103.255.254150.103.255.25565,534
105150.104.0.0/16150.104.0.1 to 150.104.255.254150.104.255.25565,534
106150.105.0.0/16150.105.0.1 to 150.105.255.254150.105.255.25565,534
107150.106.0.0/16150.106.0.1 to 150.106.255.254150.106.255.25565,534
108150.107.0.0/16150.107.0.1 to 150.107.255.254150.107.255.25565,534
109150.108.0.0/16150.108.0.1 to 150.108.255.254150.108.255.25565,534
110150.109.0.0/16150.109.0.1 to 150.109.255.254150.109.255.25565,534
111150.110.0.0/16150.110.0.1 to 150.110.255.254150.110.255.25565,534
112150.111.0.0/16150.111.0.1 to 150.111.255.254150.111.255.25565,534
113150.112.0.0/16150.112.0.1 to 150.112.255.254150.112.255.25565,534
114150.113.0.0/16150.113.0.1 to 150.113.255.254150.113.255.25565,534
115150.114.0.0/16150.114.0.1 to 150.114.255.254150.114.255.25565,534
116150.115.0.0/16150.115.0.1 to 150.115.255.254150.115.255.25565,534
117150.116.0.0/16150.116.0.1 to 150.116.255.254150.116.255.25565,534
118150.117.0.0/16150.117.0.1 to 150.117.255.254150.117.255.25565,534
119150.118.0.0/16150.118.0.1 to 150.118.255.254150.118.255.25565,534
120150.119.0.0/16150.119.0.1 to 150.119.255.254150.119.255.25565,534
121150.120.0.0/16150.120.0.1 to 150.120.255.254150.120.255.25565,534
122150.121.0.0/16150.121.0.1 to 150.121.255.254150.121.255.25565,534
123150.122.0.0/16150.122.0.1 to 150.122.255.254150.122.255.25565,534
124150.123.0.0/16150.123.0.1 to 150.123.255.254150.123.255.25565,534
125150.124.0.0/16150.124.0.1 to 150.124.255.254150.124.255.25565,534
126150.125.0.0/16150.125.0.1 to 150.125.255.254150.125.255.25565,534
127150.126.0.0/16150.126.0.1 to 150.126.255.254150.126.255.25565,534
128150.127.0.0/16150.127.0.1 to 150.127.255.254150.127.255.25565,534
129150.128.0.0/16150.128.0.1 to 150.128.255.254150.128.255.25565,534
130150.129.0.0/16150.129.0.1 to 150.129.255.254150.129.255.25565,534
131150.130.0.0/16150.130.0.1 to 150.130.255.254150.130.255.25565,534
132150.131.0.0/16150.131.0.1 to 150.131.255.254150.131.255.25565,534
133150.132.0.0/16150.132.0.1 to 150.132.255.254150.132.255.25565,534
134150.133.0.0/16150.133.0.1 to 150.133.255.254150.133.255.25565,534
135150.134.0.0/16150.134.0.1 to 150.134.255.254150.134.255.25565,534
136150.135.0.0/16150.135.0.1 to 150.135.255.254150.135.255.25565,534
137150.136.0.0/16150.136.0.1 to 150.136.255.254150.136.255.25565,534
138150.137.0.0/16150.137.0.1 to 150.137.255.254150.137.255.25565,534
139150.138.0.0/16150.138.0.1 to 150.138.255.254150.138.255.25565,534
140150.139.0.0/16150.139.0.1 to 150.139.255.254150.139.255.25565,534
141150.140.0.0/16150.140.0.1 to 150.140.255.254150.140.255.25565,534
142150.141.0.0/16150.141.0.1 to 150.141.255.254150.141.255.25565,534
143150.142.0.0/16150.142.0.1 to 150.142.255.254150.142.255.25565,534
144150.143.0.0/16150.143.0.1 to 150.143.255.254150.143.255.25565,534
145150.144.0.0/16150.144.0.1 to 150.144.255.254150.144.255.25565,534
146150.145.0.0/16150.145.0.1 to 150.145.255.254150.145.255.25565,534
147150.146.0.0/16150.146.0.1 to 150.146.255.254150.146.255.25565,534
148150.147.0.0/16150.147.0.1 to 150.147.255.254150.147.255.25565,534
149150.148.0.0/16150.148.0.1 to 150.148.255.254150.148.255.25565,534
150150.149.0.0/16150.149.0.1 to 150.149.255.254150.149.255.25565,534
151150.150.0.0/16150.150.0.1 to 150.150.255.254150.150.255.25565,534
152150.151.0.0/16150.151.0.1 to 150.151.255.254150.151.255.25565,534
153150.152.0.0/16150.152.0.1 to 150.152.255.254150.152.255.25565,534
154150.153.0.0/16150.153.0.1 to 150.153.255.254150.153.255.25565,534
155150.154.0.0/16150.154.0.1 to 150.154.255.254150.154.255.25565,534
156150.155.0.0/16150.155.0.1 to 150.155.255.254150.155.255.25565,534
157150.156.0.0/16150.156.0.1 to 150.156.255.254150.156.255.25565,534
158150.157.0.0/16150.157.0.1 to 150.157.255.254150.157.255.25565,534
159150.158.0.0/16150.158.0.1 to 150.158.255.254150.158.255.25565,534
160150.159.0.0/16150.159.0.1 to 150.159.255.254150.159.255.25565,534
161150.160.0.0/16150.160.0.1 to 150.160.255.254150.160.255.25565,534
162150.161.0.0/16150.161.0.1 to 150.161.255.254150.161.255.25565,534
163150.162.0.0/16150.162.0.1 to 150.162.255.254150.162.255.25565,534
164150.163.0.0/16150.163.0.1 to 150.163.255.254150.163.255.25565,534
165150.164.0.0/16150.164.0.1 to 150.164.255.254150.164.255.25565,534
166150.165.0.0/16150.165.0.1 to 150.165.255.254150.165.255.25565,534
167150.166.0.0/16150.166.0.1 to 150.166.255.254150.166.255.25565,534
168150.167.0.0/16150.167.0.1 to 150.167.255.254150.167.255.25565,534
169150.168.0.0/16150.168.0.1 to 150.168.255.254150.168.255.25565,534
170150.169.0.0/16150.169.0.1 to 150.169.255.254150.169.255.25565,534
171150.170.0.0/16150.170.0.1 to 150.170.255.254150.170.255.25565,534
172150.171.0.0/16150.171.0.1 to 150.171.255.254150.171.255.25565,534
173150.172.0.0/16150.172.0.1 to 150.172.255.254150.172.255.25565,534
174150.173.0.0/16150.173.0.1 to 150.173.255.254150.173.255.25565,534
175150.174.0.0/16150.174.0.1 to 150.174.255.254150.174.255.25565,534
176150.175.0.0/16150.175.0.1 to 150.175.255.254150.175.255.25565,534
177150.176.0.0/16150.176.0.1 to 150.176.255.254150.176.255.25565,534
178150.177.0.0/16150.177.0.1 to 150.177.255.254150.177.255.25565,534
179150.178.0.0/16150.178.0.1 to 150.178.255.254150.178.255.25565,534
180150.179.0.0/16150.179.0.1 to 150.179.255.254150.179.255.25565,534
181150.180.0.0/16150.180.0.1 to 150.180.255.254150.180.255.25565,534
182150.181.0.0/16150.181.0.1 to 150.181.255.254150.181.255.25565,534
183150.182.0.0/16150.182.0.1 to 150.182.255.254150.182.255.25565,534
184150.183.0.0/16150.183.0.1 to 150.183.255.254150.183.255.25565,534
185150.184.0.0/16150.184.0.1 to 150.184.255.254150.184.255.25565,534
186150.185.0.0/16150.185.0.1 to 150.185.255.254150.185.255.25565,534
187150.186.0.0/16150.186.0.1 to 150.186.255.254150.186.255.25565,534
188150.187.0.0/16150.187.0.1 to 150.187.255.254150.187.255.25565,534
189150.188.0.0/16150.188.0.1 to 150.188.255.254150.188.255.25565,534
190150.189.0.0/16150.189.0.1 to 150.189.255.254150.189.255.25565,534
191150.190.0.0/16150.190.0.1 to 150.190.255.254150.190.255.25565,534
192150.191.0.0/16150.191.0.1 to 150.191.255.254150.191.255.25565,534
193150.192.0.0/16150.192.0.1 to 150.192.255.254150.192.255.25565,534
194150.193.0.0/16150.193.0.1 to 150.193.255.254150.193.255.25565,534
195150.194.0.0/16150.194.0.1 to 150.194.255.254150.194.255.25565,534
196150.195.0.0/16150.195.0.1 to 150.195.255.254150.195.255.25565,534
197150.196.0.0/16150.196.0.1 to 150.196.255.254150.196.255.25565,534
198150.197.0.0/16150.197.0.1 to 150.197.255.254150.197.255.25565,534
199150.198.0.0/16150.198.0.1 to 150.198.255.254150.198.255.25565,534
200150.199.0.0/16150.199.0.1 to 150.199.255.254150.199.255.25565,534
201150.200.0.0/16150.200.0.1 to 150.200.255.254150.200.255.25565,534
202150.201.0.0/16150.201.0.1 to 150.201.255.254150.201.255.25565,534
203150.202.0.0/16150.202.0.1 to 150.202.255.254150.202.255.25565,534
204150.203.0.0/16150.203.0.1 to 150.203.255.254150.203.255.25565,534
205150.204.0.0/16150.204.0.1 to 150.204.255.254150.204.255.25565,534
206150.205.0.0/16150.205.0.1 to 150.205.255.254150.205.255.25565,534
207150.206.0.0/16150.206.0.1 to 150.206.255.254150.206.255.25565,534
208150.207.0.0/16150.207.0.1 to 150.207.255.254150.207.255.25565,534
209150.208.0.0/16150.208.0.1 to 150.208.255.254150.208.255.25565,534
210150.209.0.0/16150.209.0.1 to 150.209.255.254150.209.255.25565,534
211150.210.0.0/16150.210.0.1 to 150.210.255.254150.210.255.25565,534
212150.211.0.0/16150.211.0.1 to 150.211.255.254150.211.255.25565,534
213150.212.0.0/16150.212.0.1 to 150.212.255.254150.212.255.25565,534
214150.213.0.0/16150.213.0.1 to 150.213.255.254150.213.255.25565,534
215150.214.0.0/16150.214.0.1 to 150.214.255.254150.214.255.25565,534
216150.215.0.0/16150.215.0.1 to 150.215.255.254150.215.255.25565,534
217150.216.0.0/16150.216.0.1 to 150.216.255.254150.216.255.25565,534
218150.217.0.0/16150.217.0.1 to 150.217.255.254150.217.255.25565,534
219150.218.0.0/16150.218.0.1 to 150.218.255.254150.218.255.25565,534
220150.219.0.0/16150.219.0.1 to 150.219.255.254150.219.255.25565,534
221150.220.0.0/16150.220.0.1 to 150.220.255.254150.220.255.25565,534
222150.221.0.0/16150.221.0.1 to 150.221.255.254150.221.255.25565,534
223150.222.0.0/16150.222.0.1 to 150.222.255.254150.222.255.25565,534
224150.223.0.0/16150.223.0.1 to 150.223.255.254150.223.255.25565,534
225150.224.0.0/16150.224.0.1 to 150.224.255.254150.224.255.25565,534
226150.225.0.0/16150.225.0.1 to 150.225.255.254150.225.255.25565,534
227150.226.0.0/16150.226.0.1 to 150.226.255.254150.226.255.25565,534
228150.227.0.0/16150.227.0.1 to 150.227.255.254150.227.255.25565,534
229150.228.0.0/16150.228.0.1 to 150.228.255.254150.228.255.25565,534
230150.229.0.0/16150.229.0.1 to 150.229.255.254150.229.255.25565,534
231150.230.0.0/16150.230.0.1 to 150.230.255.254150.230.255.25565,534
232150.231.0.0/16150.231.0.1 to 150.231.255.254150.231.255.25565,534
233150.232.0.0/16150.232.0.1 to 150.232.255.254150.232.255.25565,534
234150.233.0.0/16150.233.0.1 to 150.233.255.254150.233.255.25565,534
235150.234.0.0/16150.234.0.1 to 150.234.255.254150.234.255.25565,534
236150.235.0.0/16150.235.0.1 to 150.235.255.254150.235.255.25565,534
237150.236.0.0/16150.236.0.1 to 150.236.255.254150.236.255.25565,534
238150.237.0.0/16150.237.0.1 to 150.237.255.254150.237.255.25565,534
239150.238.0.0/16150.238.0.1 to 150.238.255.254150.238.255.25565,534
240150.239.0.0/16150.239.0.1 to 150.239.255.254150.239.255.25565,534
241150.240.0.0/16150.240.0.1 to 150.240.255.254150.240.255.25565,534
242150.241.0.0/16150.241.0.1 to 150.241.255.254150.241.255.25565,534
243150.242.0.0/16150.242.0.1 to 150.242.255.254150.242.255.25565,534
244150.243.0.0/16150.243.0.1 to 150.243.255.254150.243.255.25565,534
245150.244.0.0/16150.244.0.1 to 150.244.255.254150.244.255.25565,534
246150.245.0.0/16150.245.0.1 to 150.245.255.254150.245.255.25565,534
247150.246.0.0/16150.246.0.1 to 150.246.255.254150.246.255.25565,534
248150.247.0.0/16150.247.0.1 to 150.247.255.254150.247.255.25565,534
249150.248.0.0/16150.248.0.1 to 150.248.255.254150.248.255.25565,534
250150.249.0.0/16150.249.0.1 to 150.249.255.254150.249.255.25565,534
251150.250.0.0/16150.250.0.1 to 150.250.255.254150.250.255.25565,534
252150.251.0.0/16150.251.0.1 to 150.251.255.254150.251.255.25565,534
253150.252.0.0/16150.252.0.1 to 150.252.255.254150.252.255.25565,534
254150.253.0.0/16150.253.0.1 to 150.253.255.254150.253.255.25565,534
255150.254.0.0/16150.254.0.1 to 150.254.255.254150.254.255.25565,534
256150.255.0.0/16150.255.0.1 to 150.255.255.254150.255.255.25565,534

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.