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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.

Network150.64.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
150.64.0.0
Broadcast address
150.71.255.255
First usable
150.64.0.1
Last usable
150.71.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
B (default /16)
As numbers
Hex 96400000 · Integer 2520776704 to 2521300991
Reverse DNS zones
64.150.in-addr.arpa
65.150.in-addr.arpa
66.150.in-addr.arpa
67.150.in-addr.arpa
68.150.in-addr.arpa
69.150.in-addr.arpa
70.150.in-addr.arpa
71.150.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010110.01000000.00000000.00000000150.64.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10010110.01000000.00000000.00000000150.64.0.0
Broadcast10010110.01000111.11111111.11111111150.71.255.255
Split into smaller subnets/23
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

150.64.0.0/13 makes 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1150.64.0.0/23150.64.0.1 to 150.64.1.254150.64.1.255510
2150.64.2.0/23150.64.2.1 to 150.64.3.254150.64.3.255510
3150.64.4.0/23150.64.4.1 to 150.64.5.254150.64.5.255510
4150.64.6.0/23150.64.6.1 to 150.64.7.254150.64.7.255510
5150.64.8.0/23150.64.8.1 to 150.64.9.254150.64.9.255510
6150.64.10.0/23150.64.10.1 to 150.64.11.254150.64.11.255510
7150.64.12.0/23150.64.12.1 to 150.64.13.254150.64.13.255510
8150.64.14.0/23150.64.14.1 to 150.64.15.254150.64.15.255510
9150.64.16.0/23150.64.16.1 to 150.64.17.254150.64.17.255510
10150.64.18.0/23150.64.18.1 to 150.64.19.254150.64.19.255510
11150.64.20.0/23150.64.20.1 to 150.64.21.254150.64.21.255510
12150.64.22.0/23150.64.22.1 to 150.64.23.254150.64.23.255510
13150.64.24.0/23150.64.24.1 to 150.64.25.254150.64.25.255510
14150.64.26.0/23150.64.26.1 to 150.64.27.254150.64.27.255510
15150.64.28.0/23150.64.28.1 to 150.64.29.254150.64.29.255510
16150.64.30.0/23150.64.30.1 to 150.64.31.254150.64.31.255510
17150.64.32.0/23150.64.32.1 to 150.64.33.254150.64.33.255510
18150.64.34.0/23150.64.34.1 to 150.64.35.254150.64.35.255510
19150.64.36.0/23150.64.36.1 to 150.64.37.254150.64.37.255510
20150.64.38.0/23150.64.38.1 to 150.64.39.254150.64.39.255510
21150.64.40.0/23150.64.40.1 to 150.64.41.254150.64.41.255510
22150.64.42.0/23150.64.42.1 to 150.64.43.254150.64.43.255510
23150.64.44.0/23150.64.44.1 to 150.64.45.254150.64.45.255510
24150.64.46.0/23150.64.46.1 to 150.64.47.254150.64.47.255510
25150.64.48.0/23150.64.48.1 to 150.64.49.254150.64.49.255510
26150.64.50.0/23150.64.50.1 to 150.64.51.254150.64.51.255510
27150.64.52.0/23150.64.52.1 to 150.64.53.254150.64.53.255510
28150.64.54.0/23150.64.54.1 to 150.64.55.254150.64.55.255510
29150.64.56.0/23150.64.56.1 to 150.64.57.254150.64.57.255510
30150.64.58.0/23150.64.58.1 to 150.64.59.254150.64.59.255510
31150.64.60.0/23150.64.60.1 to 150.64.61.254150.64.61.255510
32150.64.62.0/23150.64.62.1 to 150.64.63.254150.64.63.255510
33150.64.64.0/23150.64.64.1 to 150.64.65.254150.64.65.255510
34150.64.66.0/23150.64.66.1 to 150.64.67.254150.64.67.255510
35150.64.68.0/23150.64.68.1 to 150.64.69.254150.64.69.255510
36150.64.70.0/23150.64.70.1 to 150.64.71.254150.64.71.255510
37150.64.72.0/23150.64.72.1 to 150.64.73.254150.64.73.255510
38150.64.74.0/23150.64.74.1 to 150.64.75.254150.64.75.255510
39150.64.76.0/23150.64.76.1 to 150.64.77.254150.64.77.255510
40150.64.78.0/23150.64.78.1 to 150.64.79.254150.64.79.255510
41150.64.80.0/23150.64.80.1 to 150.64.81.254150.64.81.255510
42150.64.82.0/23150.64.82.1 to 150.64.83.254150.64.83.255510
43150.64.84.0/23150.64.84.1 to 150.64.85.254150.64.85.255510
44150.64.86.0/23150.64.86.1 to 150.64.87.254150.64.87.255510
45150.64.88.0/23150.64.88.1 to 150.64.89.254150.64.89.255510
46150.64.90.0/23150.64.90.1 to 150.64.91.254150.64.91.255510
47150.64.92.0/23150.64.92.1 to 150.64.93.254150.64.93.255510
48150.64.94.0/23150.64.94.1 to 150.64.95.254150.64.95.255510
49150.64.96.0/23150.64.96.1 to 150.64.97.254150.64.97.255510
50150.64.98.0/23150.64.98.1 to 150.64.99.254150.64.99.255510
51150.64.100.0/23150.64.100.1 to 150.64.101.254150.64.101.255510
52150.64.102.0/23150.64.102.1 to 150.64.103.254150.64.103.255510
53150.64.104.0/23150.64.104.1 to 150.64.105.254150.64.105.255510
54150.64.106.0/23150.64.106.1 to 150.64.107.254150.64.107.255510
55150.64.108.0/23150.64.108.1 to 150.64.109.254150.64.109.255510
56150.64.110.0/23150.64.110.1 to 150.64.111.254150.64.111.255510
57150.64.112.0/23150.64.112.1 to 150.64.113.254150.64.113.255510
58150.64.114.0/23150.64.114.1 to 150.64.115.254150.64.115.255510
59150.64.116.0/23150.64.116.1 to 150.64.117.254150.64.117.255510
60150.64.118.0/23150.64.118.1 to 150.64.119.254150.64.119.255510
61150.64.120.0/23150.64.120.1 to 150.64.121.254150.64.121.255510
62150.64.122.0/23150.64.122.1 to 150.64.123.254150.64.123.255510
63150.64.124.0/23150.64.124.1 to 150.64.125.254150.64.125.255510
64150.64.126.0/23150.64.126.1 to 150.64.127.254150.64.127.255510
65150.64.128.0/23150.64.128.1 to 150.64.129.254150.64.129.255510
66150.64.130.0/23150.64.130.1 to 150.64.131.254150.64.131.255510
67150.64.132.0/23150.64.132.1 to 150.64.133.254150.64.133.255510
68150.64.134.0/23150.64.134.1 to 150.64.135.254150.64.135.255510
69150.64.136.0/23150.64.136.1 to 150.64.137.254150.64.137.255510
70150.64.138.0/23150.64.138.1 to 150.64.139.254150.64.139.255510
71150.64.140.0/23150.64.140.1 to 150.64.141.254150.64.141.255510
72150.64.142.0/23150.64.142.1 to 150.64.143.254150.64.143.255510
73150.64.144.0/23150.64.144.1 to 150.64.145.254150.64.145.255510
74150.64.146.0/23150.64.146.1 to 150.64.147.254150.64.147.255510
75150.64.148.0/23150.64.148.1 to 150.64.149.254150.64.149.255510
76150.64.150.0/23150.64.150.1 to 150.64.151.254150.64.151.255510
77150.64.152.0/23150.64.152.1 to 150.64.153.254150.64.153.255510
78150.64.154.0/23150.64.154.1 to 150.64.155.254150.64.155.255510
79150.64.156.0/23150.64.156.1 to 150.64.157.254150.64.157.255510
80150.64.158.0/23150.64.158.1 to 150.64.159.254150.64.159.255510
81150.64.160.0/23150.64.160.1 to 150.64.161.254150.64.161.255510
82150.64.162.0/23150.64.162.1 to 150.64.163.254150.64.163.255510
83150.64.164.0/23150.64.164.1 to 150.64.165.254150.64.165.255510
84150.64.166.0/23150.64.166.1 to 150.64.167.254150.64.167.255510
85150.64.168.0/23150.64.168.1 to 150.64.169.254150.64.169.255510
86150.64.170.0/23150.64.170.1 to 150.64.171.254150.64.171.255510
87150.64.172.0/23150.64.172.1 to 150.64.173.254150.64.173.255510
88150.64.174.0/23150.64.174.1 to 150.64.175.254150.64.175.255510
89150.64.176.0/23150.64.176.1 to 150.64.177.254150.64.177.255510
90150.64.178.0/23150.64.178.1 to 150.64.179.254150.64.179.255510
91150.64.180.0/23150.64.180.1 to 150.64.181.254150.64.181.255510
92150.64.182.0/23150.64.182.1 to 150.64.183.254150.64.183.255510
93150.64.184.0/23150.64.184.1 to 150.64.185.254150.64.185.255510
94150.64.186.0/23150.64.186.1 to 150.64.187.254150.64.187.255510
95150.64.188.0/23150.64.188.1 to 150.64.189.254150.64.189.255510
96150.64.190.0/23150.64.190.1 to 150.64.191.254150.64.191.255510
97150.64.192.0/23150.64.192.1 to 150.64.193.254150.64.193.255510
98150.64.194.0/23150.64.194.1 to 150.64.195.254150.64.195.255510
99150.64.196.0/23150.64.196.1 to 150.64.197.254150.64.197.255510
100150.64.198.0/23150.64.198.1 to 150.64.199.254150.64.199.255510
101150.64.200.0/23150.64.200.1 to 150.64.201.254150.64.201.255510
102150.64.202.0/23150.64.202.1 to 150.64.203.254150.64.203.255510
103150.64.204.0/23150.64.204.1 to 150.64.205.254150.64.205.255510
104150.64.206.0/23150.64.206.1 to 150.64.207.254150.64.207.255510
105150.64.208.0/23150.64.208.1 to 150.64.209.254150.64.209.255510
106150.64.210.0/23150.64.210.1 to 150.64.211.254150.64.211.255510
107150.64.212.0/23150.64.212.1 to 150.64.213.254150.64.213.255510
108150.64.214.0/23150.64.214.1 to 150.64.215.254150.64.215.255510
109150.64.216.0/23150.64.216.1 to 150.64.217.254150.64.217.255510
110150.64.218.0/23150.64.218.1 to 150.64.219.254150.64.219.255510
111150.64.220.0/23150.64.220.1 to 150.64.221.254150.64.221.255510
112150.64.222.0/23150.64.222.1 to 150.64.223.254150.64.223.255510
113150.64.224.0/23150.64.224.1 to 150.64.225.254150.64.225.255510
114150.64.226.0/23150.64.226.1 to 150.64.227.254150.64.227.255510
115150.64.228.0/23150.64.228.1 to 150.64.229.254150.64.229.255510
116150.64.230.0/23150.64.230.1 to 150.64.231.254150.64.231.255510
117150.64.232.0/23150.64.232.1 to 150.64.233.254150.64.233.255510
118150.64.234.0/23150.64.234.1 to 150.64.235.254150.64.235.255510
119150.64.236.0/23150.64.236.1 to 150.64.237.254150.64.237.255510
120150.64.238.0/23150.64.238.1 to 150.64.239.254150.64.239.255510
121150.64.240.0/23150.64.240.1 to 150.64.241.254150.64.241.255510
122150.64.242.0/23150.64.242.1 to 150.64.243.254150.64.243.255510
123150.64.244.0/23150.64.244.1 to 150.64.245.254150.64.245.255510
124150.64.246.0/23150.64.246.1 to 150.64.247.254150.64.247.255510
125150.64.248.0/23150.64.248.1 to 150.64.249.254150.64.249.255510
126150.64.250.0/23150.64.250.1 to 150.64.251.254150.64.251.255510
127150.64.252.0/23150.64.252.1 to 150.64.253.254150.64.253.255510
128150.64.254.0/23150.64.254.1 to 150.64.255.254150.64.255.255510
129150.65.0.0/23150.65.0.1 to 150.65.1.254150.65.1.255510
130150.65.2.0/23150.65.2.1 to 150.65.3.254150.65.3.255510
131150.65.4.0/23150.65.4.1 to 150.65.5.254150.65.5.255510
132150.65.6.0/23150.65.6.1 to 150.65.7.254150.65.7.255510
133150.65.8.0/23150.65.8.1 to 150.65.9.254150.65.9.255510
134150.65.10.0/23150.65.10.1 to 150.65.11.254150.65.11.255510
135150.65.12.0/23150.65.12.1 to 150.65.13.254150.65.13.255510
136150.65.14.0/23150.65.14.1 to 150.65.15.254150.65.15.255510
137150.65.16.0/23150.65.16.1 to 150.65.17.254150.65.17.255510
138150.65.18.0/23150.65.18.1 to 150.65.19.254150.65.19.255510
139150.65.20.0/23150.65.20.1 to 150.65.21.254150.65.21.255510
140150.65.22.0/23150.65.22.1 to 150.65.23.254150.65.23.255510
141150.65.24.0/23150.65.24.1 to 150.65.25.254150.65.25.255510
142150.65.26.0/23150.65.26.1 to 150.65.27.254150.65.27.255510
143150.65.28.0/23150.65.28.1 to 150.65.29.254150.65.29.255510
144150.65.30.0/23150.65.30.1 to 150.65.31.254150.65.31.255510
145150.65.32.0/23150.65.32.1 to 150.65.33.254150.65.33.255510
146150.65.34.0/23150.65.34.1 to 150.65.35.254150.65.35.255510
147150.65.36.0/23150.65.36.1 to 150.65.37.254150.65.37.255510
148150.65.38.0/23150.65.38.1 to 150.65.39.254150.65.39.255510
149150.65.40.0/23150.65.40.1 to 150.65.41.254150.65.41.255510
150150.65.42.0/23150.65.42.1 to 150.65.43.254150.65.43.255510
151150.65.44.0/23150.65.44.1 to 150.65.45.254150.65.45.255510
152150.65.46.0/23150.65.46.1 to 150.65.47.254150.65.47.255510
153150.65.48.0/23150.65.48.1 to 150.65.49.254150.65.49.255510
154150.65.50.0/23150.65.50.1 to 150.65.51.254150.65.51.255510
155150.65.52.0/23150.65.52.1 to 150.65.53.254150.65.53.255510
156150.65.54.0/23150.65.54.1 to 150.65.55.254150.65.55.255510
157150.65.56.0/23150.65.56.1 to 150.65.57.254150.65.57.255510
158150.65.58.0/23150.65.58.1 to 150.65.59.254150.65.59.255510
159150.65.60.0/23150.65.60.1 to 150.65.61.254150.65.61.255510
160150.65.62.0/23150.65.62.1 to 150.65.63.254150.65.63.255510
161150.65.64.0/23150.65.64.1 to 150.65.65.254150.65.65.255510
162150.65.66.0/23150.65.66.1 to 150.65.67.254150.65.67.255510
163150.65.68.0/23150.65.68.1 to 150.65.69.254150.65.69.255510
164150.65.70.0/23150.65.70.1 to 150.65.71.254150.65.71.255510
165150.65.72.0/23150.65.72.1 to 150.65.73.254150.65.73.255510
166150.65.74.0/23150.65.74.1 to 150.65.75.254150.65.75.255510
167150.65.76.0/23150.65.76.1 to 150.65.77.254150.65.77.255510
168150.65.78.0/23150.65.78.1 to 150.65.79.254150.65.79.255510
169150.65.80.0/23150.65.80.1 to 150.65.81.254150.65.81.255510
170150.65.82.0/23150.65.82.1 to 150.65.83.254150.65.83.255510
171150.65.84.0/23150.65.84.1 to 150.65.85.254150.65.85.255510
172150.65.86.0/23150.65.86.1 to 150.65.87.254150.65.87.255510
173150.65.88.0/23150.65.88.1 to 150.65.89.254150.65.89.255510
174150.65.90.0/23150.65.90.1 to 150.65.91.254150.65.91.255510
175150.65.92.0/23150.65.92.1 to 150.65.93.254150.65.93.255510
176150.65.94.0/23150.65.94.1 to 150.65.95.254150.65.95.255510
177150.65.96.0/23150.65.96.1 to 150.65.97.254150.65.97.255510
178150.65.98.0/23150.65.98.1 to 150.65.99.254150.65.99.255510
179150.65.100.0/23150.65.100.1 to 150.65.101.254150.65.101.255510
180150.65.102.0/23150.65.102.1 to 150.65.103.254150.65.103.255510
181150.65.104.0/23150.65.104.1 to 150.65.105.254150.65.105.255510
182150.65.106.0/23150.65.106.1 to 150.65.107.254150.65.107.255510
183150.65.108.0/23150.65.108.1 to 150.65.109.254150.65.109.255510
184150.65.110.0/23150.65.110.1 to 150.65.111.254150.65.111.255510
185150.65.112.0/23150.65.112.1 to 150.65.113.254150.65.113.255510
186150.65.114.0/23150.65.114.1 to 150.65.115.254150.65.115.255510
187150.65.116.0/23150.65.116.1 to 150.65.117.254150.65.117.255510
188150.65.118.0/23150.65.118.1 to 150.65.119.254150.65.119.255510
189150.65.120.0/23150.65.120.1 to 150.65.121.254150.65.121.255510
190150.65.122.0/23150.65.122.1 to 150.65.123.254150.65.123.255510
191150.65.124.0/23150.65.124.1 to 150.65.125.254150.65.125.255510
192150.65.126.0/23150.65.126.1 to 150.65.127.254150.65.127.255510
193150.65.128.0/23150.65.128.1 to 150.65.129.254150.65.129.255510
194150.65.130.0/23150.65.130.1 to 150.65.131.254150.65.131.255510
195150.65.132.0/23150.65.132.1 to 150.65.133.254150.65.133.255510
196150.65.134.0/23150.65.134.1 to 150.65.135.254150.65.135.255510
197150.65.136.0/23150.65.136.1 to 150.65.137.254150.65.137.255510
198150.65.138.0/23150.65.138.1 to 150.65.139.254150.65.139.255510
199150.65.140.0/23150.65.140.1 to 150.65.141.254150.65.141.255510
200150.65.142.0/23150.65.142.1 to 150.65.143.254150.65.143.255510
201150.65.144.0/23150.65.144.1 to 150.65.145.254150.65.145.255510
202150.65.146.0/23150.65.146.1 to 150.65.147.254150.65.147.255510
203150.65.148.0/23150.65.148.1 to 150.65.149.254150.65.149.255510
204150.65.150.0/23150.65.150.1 to 150.65.151.254150.65.151.255510
205150.65.152.0/23150.65.152.1 to 150.65.153.254150.65.153.255510
206150.65.154.0/23150.65.154.1 to 150.65.155.254150.65.155.255510
207150.65.156.0/23150.65.156.1 to 150.65.157.254150.65.157.255510
208150.65.158.0/23150.65.158.1 to 150.65.159.254150.65.159.255510
209150.65.160.0/23150.65.160.1 to 150.65.161.254150.65.161.255510
210150.65.162.0/23150.65.162.1 to 150.65.163.254150.65.163.255510
211150.65.164.0/23150.65.164.1 to 150.65.165.254150.65.165.255510
212150.65.166.0/23150.65.166.1 to 150.65.167.254150.65.167.255510
213150.65.168.0/23150.65.168.1 to 150.65.169.254150.65.169.255510
214150.65.170.0/23150.65.170.1 to 150.65.171.254150.65.171.255510
215150.65.172.0/23150.65.172.1 to 150.65.173.254150.65.173.255510
216150.65.174.0/23150.65.174.1 to 150.65.175.254150.65.175.255510
217150.65.176.0/23150.65.176.1 to 150.65.177.254150.65.177.255510
218150.65.178.0/23150.65.178.1 to 150.65.179.254150.65.179.255510
219150.65.180.0/23150.65.180.1 to 150.65.181.254150.65.181.255510
220150.65.182.0/23150.65.182.1 to 150.65.183.254150.65.183.255510
221150.65.184.0/23150.65.184.1 to 150.65.185.254150.65.185.255510
222150.65.186.0/23150.65.186.1 to 150.65.187.254150.65.187.255510
223150.65.188.0/23150.65.188.1 to 150.65.189.254150.65.189.255510
224150.65.190.0/23150.65.190.1 to 150.65.191.254150.65.191.255510
225150.65.192.0/23150.65.192.1 to 150.65.193.254150.65.193.255510
226150.65.194.0/23150.65.194.1 to 150.65.195.254150.65.195.255510
227150.65.196.0/23150.65.196.1 to 150.65.197.254150.65.197.255510
228150.65.198.0/23150.65.198.1 to 150.65.199.254150.65.199.255510
229150.65.200.0/23150.65.200.1 to 150.65.201.254150.65.201.255510
230150.65.202.0/23150.65.202.1 to 150.65.203.254150.65.203.255510
231150.65.204.0/23150.65.204.1 to 150.65.205.254150.65.205.255510
232150.65.206.0/23150.65.206.1 to 150.65.207.254150.65.207.255510
233150.65.208.0/23150.65.208.1 to 150.65.209.254150.65.209.255510
234150.65.210.0/23150.65.210.1 to 150.65.211.254150.65.211.255510
235150.65.212.0/23150.65.212.1 to 150.65.213.254150.65.213.255510
236150.65.214.0/23150.65.214.1 to 150.65.215.254150.65.215.255510
237150.65.216.0/23150.65.216.1 to 150.65.217.254150.65.217.255510
238150.65.218.0/23150.65.218.1 to 150.65.219.254150.65.219.255510
239150.65.220.0/23150.65.220.1 to 150.65.221.254150.65.221.255510
240150.65.222.0/23150.65.222.1 to 150.65.223.254150.65.223.255510
241150.65.224.0/23150.65.224.1 to 150.65.225.254150.65.225.255510
242150.65.226.0/23150.65.226.1 to 150.65.227.254150.65.227.255510
243150.65.228.0/23150.65.228.1 to 150.65.229.254150.65.229.255510
244150.65.230.0/23150.65.230.1 to 150.65.231.254150.65.231.255510
245150.65.232.0/23150.65.232.1 to 150.65.233.254150.65.233.255510
246150.65.234.0/23150.65.234.1 to 150.65.235.254150.65.235.255510
247150.65.236.0/23150.65.236.1 to 150.65.237.254150.65.237.255510
248150.65.238.0/23150.65.238.1 to 150.65.239.254150.65.239.255510
249150.65.240.0/23150.65.240.1 to 150.65.241.254150.65.241.255510
250150.65.242.0/23150.65.242.1 to 150.65.243.254150.65.243.255510
251150.65.244.0/23150.65.244.1 to 150.65.245.254150.65.245.255510
252150.65.246.0/23150.65.246.1 to 150.65.247.254150.65.247.255510
253150.65.248.0/23150.65.248.1 to 150.65.249.254150.65.249.255510
254150.65.250.0/23150.65.250.1 to 150.65.251.254150.65.251.255510
255150.65.252.0/23150.65.252.1 to 150.65.253.254150.65.253.255510
256150.65.254.0/23150.65.254.1 to 150.65.255.254150.65.255.255510

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.