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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/18
/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 2,048 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1150.0.0.0/18150.0.0.1 to 150.0.63.254150.0.63.25516,382
2150.0.64.0/18150.0.64.1 to 150.0.127.254150.0.127.25516,382
3150.0.128.0/18150.0.128.1 to 150.0.191.254150.0.191.25516,382
4150.0.192.0/18150.0.192.1 to 150.0.255.254150.0.255.25516,382
5150.1.0.0/18150.1.0.1 to 150.1.63.254150.1.63.25516,382
6150.1.64.0/18150.1.64.1 to 150.1.127.254150.1.127.25516,382
7150.1.128.0/18150.1.128.1 to 150.1.191.254150.1.191.25516,382
8150.1.192.0/18150.1.192.1 to 150.1.255.254150.1.255.25516,382
9150.2.0.0/18150.2.0.1 to 150.2.63.254150.2.63.25516,382
10150.2.64.0/18150.2.64.1 to 150.2.127.254150.2.127.25516,382
11150.2.128.0/18150.2.128.1 to 150.2.191.254150.2.191.25516,382
12150.2.192.0/18150.2.192.1 to 150.2.255.254150.2.255.25516,382
13150.3.0.0/18150.3.0.1 to 150.3.63.254150.3.63.25516,382
14150.3.64.0/18150.3.64.1 to 150.3.127.254150.3.127.25516,382
15150.3.128.0/18150.3.128.1 to 150.3.191.254150.3.191.25516,382
16150.3.192.0/18150.3.192.1 to 150.3.255.254150.3.255.25516,382
17150.4.0.0/18150.4.0.1 to 150.4.63.254150.4.63.25516,382
18150.4.64.0/18150.4.64.1 to 150.4.127.254150.4.127.25516,382
19150.4.128.0/18150.4.128.1 to 150.4.191.254150.4.191.25516,382
20150.4.192.0/18150.4.192.1 to 150.4.255.254150.4.255.25516,382
21150.5.0.0/18150.5.0.1 to 150.5.63.254150.5.63.25516,382
22150.5.64.0/18150.5.64.1 to 150.5.127.254150.5.127.25516,382
23150.5.128.0/18150.5.128.1 to 150.5.191.254150.5.191.25516,382
24150.5.192.0/18150.5.192.1 to 150.5.255.254150.5.255.25516,382
25150.6.0.0/18150.6.0.1 to 150.6.63.254150.6.63.25516,382
26150.6.64.0/18150.6.64.1 to 150.6.127.254150.6.127.25516,382
27150.6.128.0/18150.6.128.1 to 150.6.191.254150.6.191.25516,382
28150.6.192.0/18150.6.192.1 to 150.6.255.254150.6.255.25516,382
29150.7.0.0/18150.7.0.1 to 150.7.63.254150.7.63.25516,382
30150.7.64.0/18150.7.64.1 to 150.7.127.254150.7.127.25516,382
31150.7.128.0/18150.7.128.1 to 150.7.191.254150.7.191.25516,382
32150.7.192.0/18150.7.192.1 to 150.7.255.254150.7.255.25516,382
33150.8.0.0/18150.8.0.1 to 150.8.63.254150.8.63.25516,382
34150.8.64.0/18150.8.64.1 to 150.8.127.254150.8.127.25516,382
35150.8.128.0/18150.8.128.1 to 150.8.191.254150.8.191.25516,382
36150.8.192.0/18150.8.192.1 to 150.8.255.254150.8.255.25516,382
37150.9.0.0/18150.9.0.1 to 150.9.63.254150.9.63.25516,382
38150.9.64.0/18150.9.64.1 to 150.9.127.254150.9.127.25516,382
39150.9.128.0/18150.9.128.1 to 150.9.191.254150.9.191.25516,382
40150.9.192.0/18150.9.192.1 to 150.9.255.254150.9.255.25516,382
41150.10.0.0/18150.10.0.1 to 150.10.63.254150.10.63.25516,382
42150.10.64.0/18150.10.64.1 to 150.10.127.254150.10.127.25516,382
43150.10.128.0/18150.10.128.1 to 150.10.191.254150.10.191.25516,382
44150.10.192.0/18150.10.192.1 to 150.10.255.254150.10.255.25516,382
45150.11.0.0/18150.11.0.1 to 150.11.63.254150.11.63.25516,382
46150.11.64.0/18150.11.64.1 to 150.11.127.254150.11.127.25516,382
47150.11.128.0/18150.11.128.1 to 150.11.191.254150.11.191.25516,382
48150.11.192.0/18150.11.192.1 to 150.11.255.254150.11.255.25516,382
49150.12.0.0/18150.12.0.1 to 150.12.63.254150.12.63.25516,382
50150.12.64.0/18150.12.64.1 to 150.12.127.254150.12.127.25516,382
51150.12.128.0/18150.12.128.1 to 150.12.191.254150.12.191.25516,382
52150.12.192.0/18150.12.192.1 to 150.12.255.254150.12.255.25516,382
53150.13.0.0/18150.13.0.1 to 150.13.63.254150.13.63.25516,382
54150.13.64.0/18150.13.64.1 to 150.13.127.254150.13.127.25516,382
55150.13.128.0/18150.13.128.1 to 150.13.191.254150.13.191.25516,382
56150.13.192.0/18150.13.192.1 to 150.13.255.254150.13.255.25516,382
57150.14.0.0/18150.14.0.1 to 150.14.63.254150.14.63.25516,382
58150.14.64.0/18150.14.64.1 to 150.14.127.254150.14.127.25516,382
59150.14.128.0/18150.14.128.1 to 150.14.191.254150.14.191.25516,382
60150.14.192.0/18150.14.192.1 to 150.14.255.254150.14.255.25516,382
61150.15.0.0/18150.15.0.1 to 150.15.63.254150.15.63.25516,382
62150.15.64.0/18150.15.64.1 to 150.15.127.254150.15.127.25516,382
63150.15.128.0/18150.15.128.1 to 150.15.191.254150.15.191.25516,382
64150.15.192.0/18150.15.192.1 to 150.15.255.254150.15.255.25516,382
65150.16.0.0/18150.16.0.1 to 150.16.63.254150.16.63.25516,382
66150.16.64.0/18150.16.64.1 to 150.16.127.254150.16.127.25516,382
67150.16.128.0/18150.16.128.1 to 150.16.191.254150.16.191.25516,382
68150.16.192.0/18150.16.192.1 to 150.16.255.254150.16.255.25516,382
69150.17.0.0/18150.17.0.1 to 150.17.63.254150.17.63.25516,382
70150.17.64.0/18150.17.64.1 to 150.17.127.254150.17.127.25516,382
71150.17.128.0/18150.17.128.1 to 150.17.191.254150.17.191.25516,382
72150.17.192.0/18150.17.192.1 to 150.17.255.254150.17.255.25516,382
73150.18.0.0/18150.18.0.1 to 150.18.63.254150.18.63.25516,382
74150.18.64.0/18150.18.64.1 to 150.18.127.254150.18.127.25516,382
75150.18.128.0/18150.18.128.1 to 150.18.191.254150.18.191.25516,382
76150.18.192.0/18150.18.192.1 to 150.18.255.254150.18.255.25516,382
77150.19.0.0/18150.19.0.1 to 150.19.63.254150.19.63.25516,382
78150.19.64.0/18150.19.64.1 to 150.19.127.254150.19.127.25516,382
79150.19.128.0/18150.19.128.1 to 150.19.191.254150.19.191.25516,382
80150.19.192.0/18150.19.192.1 to 150.19.255.254150.19.255.25516,382
81150.20.0.0/18150.20.0.1 to 150.20.63.254150.20.63.25516,382
82150.20.64.0/18150.20.64.1 to 150.20.127.254150.20.127.25516,382
83150.20.128.0/18150.20.128.1 to 150.20.191.254150.20.191.25516,382
84150.20.192.0/18150.20.192.1 to 150.20.255.254150.20.255.25516,382
85150.21.0.0/18150.21.0.1 to 150.21.63.254150.21.63.25516,382
86150.21.64.0/18150.21.64.1 to 150.21.127.254150.21.127.25516,382
87150.21.128.0/18150.21.128.1 to 150.21.191.254150.21.191.25516,382
88150.21.192.0/18150.21.192.1 to 150.21.255.254150.21.255.25516,382
89150.22.0.0/18150.22.0.1 to 150.22.63.254150.22.63.25516,382
90150.22.64.0/18150.22.64.1 to 150.22.127.254150.22.127.25516,382
91150.22.128.0/18150.22.128.1 to 150.22.191.254150.22.191.25516,382
92150.22.192.0/18150.22.192.1 to 150.22.255.254150.22.255.25516,382
93150.23.0.0/18150.23.0.1 to 150.23.63.254150.23.63.25516,382
94150.23.64.0/18150.23.64.1 to 150.23.127.254150.23.127.25516,382
95150.23.128.0/18150.23.128.1 to 150.23.191.254150.23.191.25516,382
96150.23.192.0/18150.23.192.1 to 150.23.255.254150.23.255.25516,382
97150.24.0.0/18150.24.0.1 to 150.24.63.254150.24.63.25516,382
98150.24.64.0/18150.24.64.1 to 150.24.127.254150.24.127.25516,382
99150.24.128.0/18150.24.128.1 to 150.24.191.254150.24.191.25516,382
100150.24.192.0/18150.24.192.1 to 150.24.255.254150.24.255.25516,382
101150.25.0.0/18150.25.0.1 to 150.25.63.254150.25.63.25516,382
102150.25.64.0/18150.25.64.1 to 150.25.127.254150.25.127.25516,382
103150.25.128.0/18150.25.128.1 to 150.25.191.254150.25.191.25516,382
104150.25.192.0/18150.25.192.1 to 150.25.255.254150.25.255.25516,382
105150.26.0.0/18150.26.0.1 to 150.26.63.254150.26.63.25516,382
106150.26.64.0/18150.26.64.1 to 150.26.127.254150.26.127.25516,382
107150.26.128.0/18150.26.128.1 to 150.26.191.254150.26.191.25516,382
108150.26.192.0/18150.26.192.1 to 150.26.255.254150.26.255.25516,382
109150.27.0.0/18150.27.0.1 to 150.27.63.254150.27.63.25516,382
110150.27.64.0/18150.27.64.1 to 150.27.127.254150.27.127.25516,382
111150.27.128.0/18150.27.128.1 to 150.27.191.254150.27.191.25516,382
112150.27.192.0/18150.27.192.1 to 150.27.255.254150.27.255.25516,382
113150.28.0.0/18150.28.0.1 to 150.28.63.254150.28.63.25516,382
114150.28.64.0/18150.28.64.1 to 150.28.127.254150.28.127.25516,382
115150.28.128.0/18150.28.128.1 to 150.28.191.254150.28.191.25516,382
116150.28.192.0/18150.28.192.1 to 150.28.255.254150.28.255.25516,382
117150.29.0.0/18150.29.0.1 to 150.29.63.254150.29.63.25516,382
118150.29.64.0/18150.29.64.1 to 150.29.127.254150.29.127.25516,382
119150.29.128.0/18150.29.128.1 to 150.29.191.254150.29.191.25516,382
120150.29.192.0/18150.29.192.1 to 150.29.255.254150.29.255.25516,382
121150.30.0.0/18150.30.0.1 to 150.30.63.254150.30.63.25516,382
122150.30.64.0/18150.30.64.1 to 150.30.127.254150.30.127.25516,382
123150.30.128.0/18150.30.128.1 to 150.30.191.254150.30.191.25516,382
124150.30.192.0/18150.30.192.1 to 150.30.255.254150.30.255.25516,382
125150.31.0.0/18150.31.0.1 to 150.31.63.254150.31.63.25516,382
126150.31.64.0/18150.31.64.1 to 150.31.127.254150.31.127.25516,382
127150.31.128.0/18150.31.128.1 to 150.31.191.254150.31.191.25516,382
128150.31.192.0/18150.31.192.1 to 150.31.255.254150.31.255.25516,382
129150.32.0.0/18150.32.0.1 to 150.32.63.254150.32.63.25516,382
130150.32.64.0/18150.32.64.1 to 150.32.127.254150.32.127.25516,382
131150.32.128.0/18150.32.128.1 to 150.32.191.254150.32.191.25516,382
132150.32.192.0/18150.32.192.1 to 150.32.255.254150.32.255.25516,382
133150.33.0.0/18150.33.0.1 to 150.33.63.254150.33.63.25516,382
134150.33.64.0/18150.33.64.1 to 150.33.127.254150.33.127.25516,382
135150.33.128.0/18150.33.128.1 to 150.33.191.254150.33.191.25516,382
136150.33.192.0/18150.33.192.1 to 150.33.255.254150.33.255.25516,382
137150.34.0.0/18150.34.0.1 to 150.34.63.254150.34.63.25516,382
138150.34.64.0/18150.34.64.1 to 150.34.127.254150.34.127.25516,382
139150.34.128.0/18150.34.128.1 to 150.34.191.254150.34.191.25516,382
140150.34.192.0/18150.34.192.1 to 150.34.255.254150.34.255.25516,382
141150.35.0.0/18150.35.0.1 to 150.35.63.254150.35.63.25516,382
142150.35.64.0/18150.35.64.1 to 150.35.127.254150.35.127.25516,382
143150.35.128.0/18150.35.128.1 to 150.35.191.254150.35.191.25516,382
144150.35.192.0/18150.35.192.1 to 150.35.255.254150.35.255.25516,382
145150.36.0.0/18150.36.0.1 to 150.36.63.254150.36.63.25516,382
146150.36.64.0/18150.36.64.1 to 150.36.127.254150.36.127.25516,382
147150.36.128.0/18150.36.128.1 to 150.36.191.254150.36.191.25516,382
148150.36.192.0/18150.36.192.1 to 150.36.255.254150.36.255.25516,382
149150.37.0.0/18150.37.0.1 to 150.37.63.254150.37.63.25516,382
150150.37.64.0/18150.37.64.1 to 150.37.127.254150.37.127.25516,382
151150.37.128.0/18150.37.128.1 to 150.37.191.254150.37.191.25516,382
152150.37.192.0/18150.37.192.1 to 150.37.255.254150.37.255.25516,382
153150.38.0.0/18150.38.0.1 to 150.38.63.254150.38.63.25516,382
154150.38.64.0/18150.38.64.1 to 150.38.127.254150.38.127.25516,382
155150.38.128.0/18150.38.128.1 to 150.38.191.254150.38.191.25516,382
156150.38.192.0/18150.38.192.1 to 150.38.255.254150.38.255.25516,382
157150.39.0.0/18150.39.0.1 to 150.39.63.254150.39.63.25516,382
158150.39.64.0/18150.39.64.1 to 150.39.127.254150.39.127.25516,382
159150.39.128.0/18150.39.128.1 to 150.39.191.254150.39.191.25516,382
160150.39.192.0/18150.39.192.1 to 150.39.255.254150.39.255.25516,382
161150.40.0.0/18150.40.0.1 to 150.40.63.254150.40.63.25516,382
162150.40.64.0/18150.40.64.1 to 150.40.127.254150.40.127.25516,382
163150.40.128.0/18150.40.128.1 to 150.40.191.254150.40.191.25516,382
164150.40.192.0/18150.40.192.1 to 150.40.255.254150.40.255.25516,382
165150.41.0.0/18150.41.0.1 to 150.41.63.254150.41.63.25516,382
166150.41.64.0/18150.41.64.1 to 150.41.127.254150.41.127.25516,382
167150.41.128.0/18150.41.128.1 to 150.41.191.254150.41.191.25516,382
168150.41.192.0/18150.41.192.1 to 150.41.255.254150.41.255.25516,382
169150.42.0.0/18150.42.0.1 to 150.42.63.254150.42.63.25516,382
170150.42.64.0/18150.42.64.1 to 150.42.127.254150.42.127.25516,382
171150.42.128.0/18150.42.128.1 to 150.42.191.254150.42.191.25516,382
172150.42.192.0/18150.42.192.1 to 150.42.255.254150.42.255.25516,382
173150.43.0.0/18150.43.0.1 to 150.43.63.254150.43.63.25516,382
174150.43.64.0/18150.43.64.1 to 150.43.127.254150.43.127.25516,382
175150.43.128.0/18150.43.128.1 to 150.43.191.254150.43.191.25516,382
176150.43.192.0/18150.43.192.1 to 150.43.255.254150.43.255.25516,382
177150.44.0.0/18150.44.0.1 to 150.44.63.254150.44.63.25516,382
178150.44.64.0/18150.44.64.1 to 150.44.127.254150.44.127.25516,382
179150.44.128.0/18150.44.128.1 to 150.44.191.254150.44.191.25516,382
180150.44.192.0/18150.44.192.1 to 150.44.255.254150.44.255.25516,382
181150.45.0.0/18150.45.0.1 to 150.45.63.254150.45.63.25516,382
182150.45.64.0/18150.45.64.1 to 150.45.127.254150.45.127.25516,382
183150.45.128.0/18150.45.128.1 to 150.45.191.254150.45.191.25516,382
184150.45.192.0/18150.45.192.1 to 150.45.255.254150.45.255.25516,382
185150.46.0.0/18150.46.0.1 to 150.46.63.254150.46.63.25516,382
186150.46.64.0/18150.46.64.1 to 150.46.127.254150.46.127.25516,382
187150.46.128.0/18150.46.128.1 to 150.46.191.254150.46.191.25516,382
188150.46.192.0/18150.46.192.1 to 150.46.255.254150.46.255.25516,382
189150.47.0.0/18150.47.0.1 to 150.47.63.254150.47.63.25516,382
190150.47.64.0/18150.47.64.1 to 150.47.127.254150.47.127.25516,382
191150.47.128.0/18150.47.128.1 to 150.47.191.254150.47.191.25516,382
192150.47.192.0/18150.47.192.1 to 150.47.255.254150.47.255.25516,382
193150.48.0.0/18150.48.0.1 to 150.48.63.254150.48.63.25516,382
194150.48.64.0/18150.48.64.1 to 150.48.127.254150.48.127.25516,382
195150.48.128.0/18150.48.128.1 to 150.48.191.254150.48.191.25516,382
196150.48.192.0/18150.48.192.1 to 150.48.255.254150.48.255.25516,382
197150.49.0.0/18150.49.0.1 to 150.49.63.254150.49.63.25516,382
198150.49.64.0/18150.49.64.1 to 150.49.127.254150.49.127.25516,382
199150.49.128.0/18150.49.128.1 to 150.49.191.254150.49.191.25516,382
200150.49.192.0/18150.49.192.1 to 150.49.255.254150.49.255.25516,382
201150.50.0.0/18150.50.0.1 to 150.50.63.254150.50.63.25516,382
202150.50.64.0/18150.50.64.1 to 150.50.127.254150.50.127.25516,382
203150.50.128.0/18150.50.128.1 to 150.50.191.254150.50.191.25516,382
204150.50.192.0/18150.50.192.1 to 150.50.255.254150.50.255.25516,382
205150.51.0.0/18150.51.0.1 to 150.51.63.254150.51.63.25516,382
206150.51.64.0/18150.51.64.1 to 150.51.127.254150.51.127.25516,382
207150.51.128.0/18150.51.128.1 to 150.51.191.254150.51.191.25516,382
208150.51.192.0/18150.51.192.1 to 150.51.255.254150.51.255.25516,382
209150.52.0.0/18150.52.0.1 to 150.52.63.254150.52.63.25516,382
210150.52.64.0/18150.52.64.1 to 150.52.127.254150.52.127.25516,382
211150.52.128.0/18150.52.128.1 to 150.52.191.254150.52.191.25516,382
212150.52.192.0/18150.52.192.1 to 150.52.255.254150.52.255.25516,382
213150.53.0.0/18150.53.0.1 to 150.53.63.254150.53.63.25516,382
214150.53.64.0/18150.53.64.1 to 150.53.127.254150.53.127.25516,382
215150.53.128.0/18150.53.128.1 to 150.53.191.254150.53.191.25516,382
216150.53.192.0/18150.53.192.1 to 150.53.255.254150.53.255.25516,382
217150.54.0.0/18150.54.0.1 to 150.54.63.254150.54.63.25516,382
218150.54.64.0/18150.54.64.1 to 150.54.127.254150.54.127.25516,382
219150.54.128.0/18150.54.128.1 to 150.54.191.254150.54.191.25516,382
220150.54.192.0/18150.54.192.1 to 150.54.255.254150.54.255.25516,382
221150.55.0.0/18150.55.0.1 to 150.55.63.254150.55.63.25516,382
222150.55.64.0/18150.55.64.1 to 150.55.127.254150.55.127.25516,382
223150.55.128.0/18150.55.128.1 to 150.55.191.254150.55.191.25516,382
224150.55.192.0/18150.55.192.1 to 150.55.255.254150.55.255.25516,382
225150.56.0.0/18150.56.0.1 to 150.56.63.254150.56.63.25516,382
226150.56.64.0/18150.56.64.1 to 150.56.127.254150.56.127.25516,382
227150.56.128.0/18150.56.128.1 to 150.56.191.254150.56.191.25516,382
228150.56.192.0/18150.56.192.1 to 150.56.255.254150.56.255.25516,382
229150.57.0.0/18150.57.0.1 to 150.57.63.254150.57.63.25516,382
230150.57.64.0/18150.57.64.1 to 150.57.127.254150.57.127.25516,382
231150.57.128.0/18150.57.128.1 to 150.57.191.254150.57.191.25516,382
232150.57.192.0/18150.57.192.1 to 150.57.255.254150.57.255.25516,382
233150.58.0.0/18150.58.0.1 to 150.58.63.254150.58.63.25516,382
234150.58.64.0/18150.58.64.1 to 150.58.127.254150.58.127.25516,382
235150.58.128.0/18150.58.128.1 to 150.58.191.254150.58.191.25516,382
236150.58.192.0/18150.58.192.1 to 150.58.255.254150.58.255.25516,382
237150.59.0.0/18150.59.0.1 to 150.59.63.254150.59.63.25516,382
238150.59.64.0/18150.59.64.1 to 150.59.127.254150.59.127.25516,382
239150.59.128.0/18150.59.128.1 to 150.59.191.254150.59.191.25516,382
240150.59.192.0/18150.59.192.1 to 150.59.255.254150.59.255.25516,382
241150.60.0.0/18150.60.0.1 to 150.60.63.254150.60.63.25516,382
242150.60.64.0/18150.60.64.1 to 150.60.127.254150.60.127.25516,382
243150.60.128.0/18150.60.128.1 to 150.60.191.254150.60.191.25516,382
244150.60.192.0/18150.60.192.1 to 150.60.255.254150.60.255.25516,382
245150.61.0.0/18150.61.0.1 to 150.61.63.254150.61.63.25516,382
246150.61.64.0/18150.61.64.1 to 150.61.127.254150.61.127.25516,382
247150.61.128.0/18150.61.128.1 to 150.61.191.254150.61.191.25516,382
248150.61.192.0/18150.61.192.1 to 150.61.255.254150.61.255.25516,382
249150.62.0.0/18150.62.0.1 to 150.62.63.254150.62.63.25516,382
250150.62.64.0/18150.62.64.1 to 150.62.127.254150.62.127.25516,382
251150.62.128.0/18150.62.128.1 to 150.62.191.254150.62.191.25516,382
252150.62.192.0/18150.62.192.1 to 150.62.255.254150.62.255.25516,382
253150.63.0.0/18150.63.0.1 to 150.63.63.254150.63.63.25516,382
254150.63.64.0/18150.63.64.1 to 150.63.127.254150.63.127.25516,382
255150.63.128.0/18150.63.128.1 to 150.63.191.254150.63.191.25516,382
256150.63.192.0/18150.63.192.1 to 150.63.255.254150.63.255.25516,382

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.