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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.

Network150.26.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
150.26.0.0
Broadcast address
150.27.255.255
First usable
150.26.0.1
Last usable
150.27.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
B (default /16)
As numbers
Hex 961A0000 · Integer 2518286336 to 2518417407
Reverse DNS zones
26.150.in-addr.arpa
27.150.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010110.00011010.00000000.00000000150.26.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network10010110.00011010.00000000.00000000150.26.0.0
Broadcast10010110.00011011.11111111.11111111150.27.255.255
Split into smaller subnets/25
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

150.26.0.0/15 makes 1,024 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1150.26.0.0/25150.26.0.1 to 150.26.0.126150.26.0.127126
2150.26.0.128/25150.26.0.129 to 150.26.0.254150.26.0.255126
3150.26.1.0/25150.26.1.1 to 150.26.1.126150.26.1.127126
4150.26.1.128/25150.26.1.129 to 150.26.1.254150.26.1.255126
5150.26.2.0/25150.26.2.1 to 150.26.2.126150.26.2.127126
6150.26.2.128/25150.26.2.129 to 150.26.2.254150.26.2.255126
7150.26.3.0/25150.26.3.1 to 150.26.3.126150.26.3.127126
8150.26.3.128/25150.26.3.129 to 150.26.3.254150.26.3.255126
9150.26.4.0/25150.26.4.1 to 150.26.4.126150.26.4.127126
10150.26.4.128/25150.26.4.129 to 150.26.4.254150.26.4.255126
11150.26.5.0/25150.26.5.1 to 150.26.5.126150.26.5.127126
12150.26.5.128/25150.26.5.129 to 150.26.5.254150.26.5.255126
13150.26.6.0/25150.26.6.1 to 150.26.6.126150.26.6.127126
14150.26.6.128/25150.26.6.129 to 150.26.6.254150.26.6.255126
15150.26.7.0/25150.26.7.1 to 150.26.7.126150.26.7.127126
16150.26.7.128/25150.26.7.129 to 150.26.7.254150.26.7.255126
17150.26.8.0/25150.26.8.1 to 150.26.8.126150.26.8.127126
18150.26.8.128/25150.26.8.129 to 150.26.8.254150.26.8.255126
19150.26.9.0/25150.26.9.1 to 150.26.9.126150.26.9.127126
20150.26.9.128/25150.26.9.129 to 150.26.9.254150.26.9.255126
21150.26.10.0/25150.26.10.1 to 150.26.10.126150.26.10.127126
22150.26.10.128/25150.26.10.129 to 150.26.10.254150.26.10.255126
23150.26.11.0/25150.26.11.1 to 150.26.11.126150.26.11.127126
24150.26.11.128/25150.26.11.129 to 150.26.11.254150.26.11.255126
25150.26.12.0/25150.26.12.1 to 150.26.12.126150.26.12.127126
26150.26.12.128/25150.26.12.129 to 150.26.12.254150.26.12.255126
27150.26.13.0/25150.26.13.1 to 150.26.13.126150.26.13.127126
28150.26.13.128/25150.26.13.129 to 150.26.13.254150.26.13.255126
29150.26.14.0/25150.26.14.1 to 150.26.14.126150.26.14.127126
30150.26.14.128/25150.26.14.129 to 150.26.14.254150.26.14.255126
31150.26.15.0/25150.26.15.1 to 150.26.15.126150.26.15.127126
32150.26.15.128/25150.26.15.129 to 150.26.15.254150.26.15.255126
33150.26.16.0/25150.26.16.1 to 150.26.16.126150.26.16.127126
34150.26.16.128/25150.26.16.129 to 150.26.16.254150.26.16.255126
35150.26.17.0/25150.26.17.1 to 150.26.17.126150.26.17.127126
36150.26.17.128/25150.26.17.129 to 150.26.17.254150.26.17.255126
37150.26.18.0/25150.26.18.1 to 150.26.18.126150.26.18.127126
38150.26.18.128/25150.26.18.129 to 150.26.18.254150.26.18.255126
39150.26.19.0/25150.26.19.1 to 150.26.19.126150.26.19.127126
40150.26.19.128/25150.26.19.129 to 150.26.19.254150.26.19.255126
41150.26.20.0/25150.26.20.1 to 150.26.20.126150.26.20.127126
42150.26.20.128/25150.26.20.129 to 150.26.20.254150.26.20.255126
43150.26.21.0/25150.26.21.1 to 150.26.21.126150.26.21.127126
44150.26.21.128/25150.26.21.129 to 150.26.21.254150.26.21.255126
45150.26.22.0/25150.26.22.1 to 150.26.22.126150.26.22.127126
46150.26.22.128/25150.26.22.129 to 150.26.22.254150.26.22.255126
47150.26.23.0/25150.26.23.1 to 150.26.23.126150.26.23.127126
48150.26.23.128/25150.26.23.129 to 150.26.23.254150.26.23.255126
49150.26.24.0/25150.26.24.1 to 150.26.24.126150.26.24.127126
50150.26.24.128/25150.26.24.129 to 150.26.24.254150.26.24.255126
51150.26.25.0/25150.26.25.1 to 150.26.25.126150.26.25.127126
52150.26.25.128/25150.26.25.129 to 150.26.25.254150.26.25.255126
53150.26.26.0/25150.26.26.1 to 150.26.26.126150.26.26.127126
54150.26.26.128/25150.26.26.129 to 150.26.26.254150.26.26.255126
55150.26.27.0/25150.26.27.1 to 150.26.27.126150.26.27.127126
56150.26.27.128/25150.26.27.129 to 150.26.27.254150.26.27.255126
57150.26.28.0/25150.26.28.1 to 150.26.28.126150.26.28.127126
58150.26.28.128/25150.26.28.129 to 150.26.28.254150.26.28.255126
59150.26.29.0/25150.26.29.1 to 150.26.29.126150.26.29.127126
60150.26.29.128/25150.26.29.129 to 150.26.29.254150.26.29.255126
61150.26.30.0/25150.26.30.1 to 150.26.30.126150.26.30.127126
62150.26.30.128/25150.26.30.129 to 150.26.30.254150.26.30.255126
63150.26.31.0/25150.26.31.1 to 150.26.31.126150.26.31.127126
64150.26.31.128/25150.26.31.129 to 150.26.31.254150.26.31.255126
65150.26.32.0/25150.26.32.1 to 150.26.32.126150.26.32.127126
66150.26.32.128/25150.26.32.129 to 150.26.32.254150.26.32.255126
67150.26.33.0/25150.26.33.1 to 150.26.33.126150.26.33.127126
68150.26.33.128/25150.26.33.129 to 150.26.33.254150.26.33.255126
69150.26.34.0/25150.26.34.1 to 150.26.34.126150.26.34.127126
70150.26.34.128/25150.26.34.129 to 150.26.34.254150.26.34.255126
71150.26.35.0/25150.26.35.1 to 150.26.35.126150.26.35.127126
72150.26.35.128/25150.26.35.129 to 150.26.35.254150.26.35.255126
73150.26.36.0/25150.26.36.1 to 150.26.36.126150.26.36.127126
74150.26.36.128/25150.26.36.129 to 150.26.36.254150.26.36.255126
75150.26.37.0/25150.26.37.1 to 150.26.37.126150.26.37.127126
76150.26.37.128/25150.26.37.129 to 150.26.37.254150.26.37.255126
77150.26.38.0/25150.26.38.1 to 150.26.38.126150.26.38.127126
78150.26.38.128/25150.26.38.129 to 150.26.38.254150.26.38.255126
79150.26.39.0/25150.26.39.1 to 150.26.39.126150.26.39.127126
80150.26.39.128/25150.26.39.129 to 150.26.39.254150.26.39.255126
81150.26.40.0/25150.26.40.1 to 150.26.40.126150.26.40.127126
82150.26.40.128/25150.26.40.129 to 150.26.40.254150.26.40.255126
83150.26.41.0/25150.26.41.1 to 150.26.41.126150.26.41.127126
84150.26.41.128/25150.26.41.129 to 150.26.41.254150.26.41.255126
85150.26.42.0/25150.26.42.1 to 150.26.42.126150.26.42.127126
86150.26.42.128/25150.26.42.129 to 150.26.42.254150.26.42.255126
87150.26.43.0/25150.26.43.1 to 150.26.43.126150.26.43.127126
88150.26.43.128/25150.26.43.129 to 150.26.43.254150.26.43.255126
89150.26.44.0/25150.26.44.1 to 150.26.44.126150.26.44.127126
90150.26.44.128/25150.26.44.129 to 150.26.44.254150.26.44.255126
91150.26.45.0/25150.26.45.1 to 150.26.45.126150.26.45.127126
92150.26.45.128/25150.26.45.129 to 150.26.45.254150.26.45.255126
93150.26.46.0/25150.26.46.1 to 150.26.46.126150.26.46.127126
94150.26.46.128/25150.26.46.129 to 150.26.46.254150.26.46.255126
95150.26.47.0/25150.26.47.1 to 150.26.47.126150.26.47.127126
96150.26.47.128/25150.26.47.129 to 150.26.47.254150.26.47.255126
97150.26.48.0/25150.26.48.1 to 150.26.48.126150.26.48.127126
98150.26.48.128/25150.26.48.129 to 150.26.48.254150.26.48.255126
99150.26.49.0/25150.26.49.1 to 150.26.49.126150.26.49.127126
100150.26.49.128/25150.26.49.129 to 150.26.49.254150.26.49.255126
101150.26.50.0/25150.26.50.1 to 150.26.50.126150.26.50.127126
102150.26.50.128/25150.26.50.129 to 150.26.50.254150.26.50.255126
103150.26.51.0/25150.26.51.1 to 150.26.51.126150.26.51.127126
104150.26.51.128/25150.26.51.129 to 150.26.51.254150.26.51.255126
105150.26.52.0/25150.26.52.1 to 150.26.52.126150.26.52.127126
106150.26.52.128/25150.26.52.129 to 150.26.52.254150.26.52.255126
107150.26.53.0/25150.26.53.1 to 150.26.53.126150.26.53.127126
108150.26.53.128/25150.26.53.129 to 150.26.53.254150.26.53.255126
109150.26.54.0/25150.26.54.1 to 150.26.54.126150.26.54.127126
110150.26.54.128/25150.26.54.129 to 150.26.54.254150.26.54.255126
111150.26.55.0/25150.26.55.1 to 150.26.55.126150.26.55.127126
112150.26.55.128/25150.26.55.129 to 150.26.55.254150.26.55.255126
113150.26.56.0/25150.26.56.1 to 150.26.56.126150.26.56.127126
114150.26.56.128/25150.26.56.129 to 150.26.56.254150.26.56.255126
115150.26.57.0/25150.26.57.1 to 150.26.57.126150.26.57.127126
116150.26.57.128/25150.26.57.129 to 150.26.57.254150.26.57.255126
117150.26.58.0/25150.26.58.1 to 150.26.58.126150.26.58.127126
118150.26.58.128/25150.26.58.129 to 150.26.58.254150.26.58.255126
119150.26.59.0/25150.26.59.1 to 150.26.59.126150.26.59.127126
120150.26.59.128/25150.26.59.129 to 150.26.59.254150.26.59.255126
121150.26.60.0/25150.26.60.1 to 150.26.60.126150.26.60.127126
122150.26.60.128/25150.26.60.129 to 150.26.60.254150.26.60.255126
123150.26.61.0/25150.26.61.1 to 150.26.61.126150.26.61.127126
124150.26.61.128/25150.26.61.129 to 150.26.61.254150.26.61.255126
125150.26.62.0/25150.26.62.1 to 150.26.62.126150.26.62.127126
126150.26.62.128/25150.26.62.129 to 150.26.62.254150.26.62.255126
127150.26.63.0/25150.26.63.1 to 150.26.63.126150.26.63.127126
128150.26.63.128/25150.26.63.129 to 150.26.63.254150.26.63.255126
129150.26.64.0/25150.26.64.1 to 150.26.64.126150.26.64.127126
130150.26.64.128/25150.26.64.129 to 150.26.64.254150.26.64.255126
131150.26.65.0/25150.26.65.1 to 150.26.65.126150.26.65.127126
132150.26.65.128/25150.26.65.129 to 150.26.65.254150.26.65.255126
133150.26.66.0/25150.26.66.1 to 150.26.66.126150.26.66.127126
134150.26.66.128/25150.26.66.129 to 150.26.66.254150.26.66.255126
135150.26.67.0/25150.26.67.1 to 150.26.67.126150.26.67.127126
136150.26.67.128/25150.26.67.129 to 150.26.67.254150.26.67.255126
137150.26.68.0/25150.26.68.1 to 150.26.68.126150.26.68.127126
138150.26.68.128/25150.26.68.129 to 150.26.68.254150.26.68.255126
139150.26.69.0/25150.26.69.1 to 150.26.69.126150.26.69.127126
140150.26.69.128/25150.26.69.129 to 150.26.69.254150.26.69.255126
141150.26.70.0/25150.26.70.1 to 150.26.70.126150.26.70.127126
142150.26.70.128/25150.26.70.129 to 150.26.70.254150.26.70.255126
143150.26.71.0/25150.26.71.1 to 150.26.71.126150.26.71.127126
144150.26.71.128/25150.26.71.129 to 150.26.71.254150.26.71.255126
145150.26.72.0/25150.26.72.1 to 150.26.72.126150.26.72.127126
146150.26.72.128/25150.26.72.129 to 150.26.72.254150.26.72.255126
147150.26.73.0/25150.26.73.1 to 150.26.73.126150.26.73.127126
148150.26.73.128/25150.26.73.129 to 150.26.73.254150.26.73.255126
149150.26.74.0/25150.26.74.1 to 150.26.74.126150.26.74.127126
150150.26.74.128/25150.26.74.129 to 150.26.74.254150.26.74.255126
151150.26.75.0/25150.26.75.1 to 150.26.75.126150.26.75.127126
152150.26.75.128/25150.26.75.129 to 150.26.75.254150.26.75.255126
153150.26.76.0/25150.26.76.1 to 150.26.76.126150.26.76.127126
154150.26.76.128/25150.26.76.129 to 150.26.76.254150.26.76.255126
155150.26.77.0/25150.26.77.1 to 150.26.77.126150.26.77.127126
156150.26.77.128/25150.26.77.129 to 150.26.77.254150.26.77.255126
157150.26.78.0/25150.26.78.1 to 150.26.78.126150.26.78.127126
158150.26.78.128/25150.26.78.129 to 150.26.78.254150.26.78.255126
159150.26.79.0/25150.26.79.1 to 150.26.79.126150.26.79.127126
160150.26.79.128/25150.26.79.129 to 150.26.79.254150.26.79.255126
161150.26.80.0/25150.26.80.1 to 150.26.80.126150.26.80.127126
162150.26.80.128/25150.26.80.129 to 150.26.80.254150.26.80.255126
163150.26.81.0/25150.26.81.1 to 150.26.81.126150.26.81.127126
164150.26.81.128/25150.26.81.129 to 150.26.81.254150.26.81.255126
165150.26.82.0/25150.26.82.1 to 150.26.82.126150.26.82.127126
166150.26.82.128/25150.26.82.129 to 150.26.82.254150.26.82.255126
167150.26.83.0/25150.26.83.1 to 150.26.83.126150.26.83.127126
168150.26.83.128/25150.26.83.129 to 150.26.83.254150.26.83.255126
169150.26.84.0/25150.26.84.1 to 150.26.84.126150.26.84.127126
170150.26.84.128/25150.26.84.129 to 150.26.84.254150.26.84.255126
171150.26.85.0/25150.26.85.1 to 150.26.85.126150.26.85.127126
172150.26.85.128/25150.26.85.129 to 150.26.85.254150.26.85.255126
173150.26.86.0/25150.26.86.1 to 150.26.86.126150.26.86.127126
174150.26.86.128/25150.26.86.129 to 150.26.86.254150.26.86.255126
175150.26.87.0/25150.26.87.1 to 150.26.87.126150.26.87.127126
176150.26.87.128/25150.26.87.129 to 150.26.87.254150.26.87.255126
177150.26.88.0/25150.26.88.1 to 150.26.88.126150.26.88.127126
178150.26.88.128/25150.26.88.129 to 150.26.88.254150.26.88.255126
179150.26.89.0/25150.26.89.1 to 150.26.89.126150.26.89.127126
180150.26.89.128/25150.26.89.129 to 150.26.89.254150.26.89.255126
181150.26.90.0/25150.26.90.1 to 150.26.90.126150.26.90.127126
182150.26.90.128/25150.26.90.129 to 150.26.90.254150.26.90.255126
183150.26.91.0/25150.26.91.1 to 150.26.91.126150.26.91.127126
184150.26.91.128/25150.26.91.129 to 150.26.91.254150.26.91.255126
185150.26.92.0/25150.26.92.1 to 150.26.92.126150.26.92.127126
186150.26.92.128/25150.26.92.129 to 150.26.92.254150.26.92.255126
187150.26.93.0/25150.26.93.1 to 150.26.93.126150.26.93.127126
188150.26.93.128/25150.26.93.129 to 150.26.93.254150.26.93.255126
189150.26.94.0/25150.26.94.1 to 150.26.94.126150.26.94.127126
190150.26.94.128/25150.26.94.129 to 150.26.94.254150.26.94.255126
191150.26.95.0/25150.26.95.1 to 150.26.95.126150.26.95.127126
192150.26.95.128/25150.26.95.129 to 150.26.95.254150.26.95.255126
193150.26.96.0/25150.26.96.1 to 150.26.96.126150.26.96.127126
194150.26.96.128/25150.26.96.129 to 150.26.96.254150.26.96.255126
195150.26.97.0/25150.26.97.1 to 150.26.97.126150.26.97.127126
196150.26.97.128/25150.26.97.129 to 150.26.97.254150.26.97.255126
197150.26.98.0/25150.26.98.1 to 150.26.98.126150.26.98.127126
198150.26.98.128/25150.26.98.129 to 150.26.98.254150.26.98.255126
199150.26.99.0/25150.26.99.1 to 150.26.99.126150.26.99.127126
200150.26.99.128/25150.26.99.129 to 150.26.99.254150.26.99.255126
201150.26.100.0/25150.26.100.1 to 150.26.100.126150.26.100.127126
202150.26.100.128/25150.26.100.129 to 150.26.100.254150.26.100.255126
203150.26.101.0/25150.26.101.1 to 150.26.101.126150.26.101.127126
204150.26.101.128/25150.26.101.129 to 150.26.101.254150.26.101.255126
205150.26.102.0/25150.26.102.1 to 150.26.102.126150.26.102.127126
206150.26.102.128/25150.26.102.129 to 150.26.102.254150.26.102.255126
207150.26.103.0/25150.26.103.1 to 150.26.103.126150.26.103.127126
208150.26.103.128/25150.26.103.129 to 150.26.103.254150.26.103.255126
209150.26.104.0/25150.26.104.1 to 150.26.104.126150.26.104.127126
210150.26.104.128/25150.26.104.129 to 150.26.104.254150.26.104.255126
211150.26.105.0/25150.26.105.1 to 150.26.105.126150.26.105.127126
212150.26.105.128/25150.26.105.129 to 150.26.105.254150.26.105.255126
213150.26.106.0/25150.26.106.1 to 150.26.106.126150.26.106.127126
214150.26.106.128/25150.26.106.129 to 150.26.106.254150.26.106.255126
215150.26.107.0/25150.26.107.1 to 150.26.107.126150.26.107.127126
216150.26.107.128/25150.26.107.129 to 150.26.107.254150.26.107.255126
217150.26.108.0/25150.26.108.1 to 150.26.108.126150.26.108.127126
218150.26.108.128/25150.26.108.129 to 150.26.108.254150.26.108.255126
219150.26.109.0/25150.26.109.1 to 150.26.109.126150.26.109.127126
220150.26.109.128/25150.26.109.129 to 150.26.109.254150.26.109.255126
221150.26.110.0/25150.26.110.1 to 150.26.110.126150.26.110.127126
222150.26.110.128/25150.26.110.129 to 150.26.110.254150.26.110.255126
223150.26.111.0/25150.26.111.1 to 150.26.111.126150.26.111.127126
224150.26.111.128/25150.26.111.129 to 150.26.111.254150.26.111.255126
225150.26.112.0/25150.26.112.1 to 150.26.112.126150.26.112.127126
226150.26.112.128/25150.26.112.129 to 150.26.112.254150.26.112.255126
227150.26.113.0/25150.26.113.1 to 150.26.113.126150.26.113.127126
228150.26.113.128/25150.26.113.129 to 150.26.113.254150.26.113.255126
229150.26.114.0/25150.26.114.1 to 150.26.114.126150.26.114.127126
230150.26.114.128/25150.26.114.129 to 150.26.114.254150.26.114.255126
231150.26.115.0/25150.26.115.1 to 150.26.115.126150.26.115.127126
232150.26.115.128/25150.26.115.129 to 150.26.115.254150.26.115.255126
233150.26.116.0/25150.26.116.1 to 150.26.116.126150.26.116.127126
234150.26.116.128/25150.26.116.129 to 150.26.116.254150.26.116.255126
235150.26.117.0/25150.26.117.1 to 150.26.117.126150.26.117.127126
236150.26.117.128/25150.26.117.129 to 150.26.117.254150.26.117.255126
237150.26.118.0/25150.26.118.1 to 150.26.118.126150.26.118.127126
238150.26.118.128/25150.26.118.129 to 150.26.118.254150.26.118.255126
239150.26.119.0/25150.26.119.1 to 150.26.119.126150.26.119.127126
240150.26.119.128/25150.26.119.129 to 150.26.119.254150.26.119.255126
241150.26.120.0/25150.26.120.1 to 150.26.120.126150.26.120.127126
242150.26.120.128/25150.26.120.129 to 150.26.120.254150.26.120.255126
243150.26.121.0/25150.26.121.1 to 150.26.121.126150.26.121.127126
244150.26.121.128/25150.26.121.129 to 150.26.121.254150.26.121.255126
245150.26.122.0/25150.26.122.1 to 150.26.122.126150.26.122.127126
246150.26.122.128/25150.26.122.129 to 150.26.122.254150.26.122.255126
247150.26.123.0/25150.26.123.1 to 150.26.123.126150.26.123.127126
248150.26.123.128/25150.26.123.129 to 150.26.123.254150.26.123.255126
249150.26.124.0/25150.26.124.1 to 150.26.124.126150.26.124.127126
250150.26.124.128/25150.26.124.129 to 150.26.124.254150.26.124.255126
251150.26.125.0/25150.26.125.1 to 150.26.125.126150.26.125.127126
252150.26.125.128/25150.26.125.129 to 150.26.125.254150.26.125.255126
253150.26.126.0/25150.26.126.1 to 150.26.126.126150.26.126.127126
254150.26.126.128/25150.26.126.129 to 150.26.126.254150.26.126.255126
255150.26.127.0/25150.26.127.1 to 150.26.127.126150.26.127.127126
256150.26.127.128/25150.26.127.129 to 150.26.127.254150.26.127.255126

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.