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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.

Network126.232.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
126.232.0.0
Broadcast address
126.239.255.255
First usable
126.232.0.1
Last usable
126.239.255.254
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
A (default /8)
As numbers
Hex 7EE80000 · Integer 2129133568 to 2129657855
Reverse DNS zones
232.126.in-addr.arpa
233.126.in-addr.arpa
234.126.in-addr.arpa
235.126.in-addr.arpa
236.126.in-addr.arpa
237.126.in-addr.arpa
238.126.in-addr.arpa
239.126.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
Address01111110.11101000.00000000.00000000126.232.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01111110.11101000.00000000.00000000126.232.0.0
Broadcast01111110.11101111.11111111.11111111126.239.255.255
Split into smaller subnets/22
/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)

126.232.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1126.232.0.0/22126.232.0.1 to 126.232.3.254126.232.3.2551,022
2126.232.4.0/22126.232.4.1 to 126.232.7.254126.232.7.2551,022
3126.232.8.0/22126.232.8.1 to 126.232.11.254126.232.11.2551,022
4126.232.12.0/22126.232.12.1 to 126.232.15.254126.232.15.2551,022
5126.232.16.0/22126.232.16.1 to 126.232.19.254126.232.19.2551,022
6126.232.20.0/22126.232.20.1 to 126.232.23.254126.232.23.2551,022
7126.232.24.0/22126.232.24.1 to 126.232.27.254126.232.27.2551,022
8126.232.28.0/22126.232.28.1 to 126.232.31.254126.232.31.2551,022
9126.232.32.0/22126.232.32.1 to 126.232.35.254126.232.35.2551,022
10126.232.36.0/22126.232.36.1 to 126.232.39.254126.232.39.2551,022
11126.232.40.0/22126.232.40.1 to 126.232.43.254126.232.43.2551,022
12126.232.44.0/22126.232.44.1 to 126.232.47.254126.232.47.2551,022
13126.232.48.0/22126.232.48.1 to 126.232.51.254126.232.51.2551,022
14126.232.52.0/22126.232.52.1 to 126.232.55.254126.232.55.2551,022
15126.232.56.0/22126.232.56.1 to 126.232.59.254126.232.59.2551,022
16126.232.60.0/22126.232.60.1 to 126.232.63.254126.232.63.2551,022
17126.232.64.0/22126.232.64.1 to 126.232.67.254126.232.67.2551,022
18126.232.68.0/22126.232.68.1 to 126.232.71.254126.232.71.2551,022
19126.232.72.0/22126.232.72.1 to 126.232.75.254126.232.75.2551,022
20126.232.76.0/22126.232.76.1 to 126.232.79.254126.232.79.2551,022
21126.232.80.0/22126.232.80.1 to 126.232.83.254126.232.83.2551,022
22126.232.84.0/22126.232.84.1 to 126.232.87.254126.232.87.2551,022
23126.232.88.0/22126.232.88.1 to 126.232.91.254126.232.91.2551,022
24126.232.92.0/22126.232.92.1 to 126.232.95.254126.232.95.2551,022
25126.232.96.0/22126.232.96.1 to 126.232.99.254126.232.99.2551,022
26126.232.100.0/22126.232.100.1 to 126.232.103.254126.232.103.2551,022
27126.232.104.0/22126.232.104.1 to 126.232.107.254126.232.107.2551,022
28126.232.108.0/22126.232.108.1 to 126.232.111.254126.232.111.2551,022
29126.232.112.0/22126.232.112.1 to 126.232.115.254126.232.115.2551,022
30126.232.116.0/22126.232.116.1 to 126.232.119.254126.232.119.2551,022
31126.232.120.0/22126.232.120.1 to 126.232.123.254126.232.123.2551,022
32126.232.124.0/22126.232.124.1 to 126.232.127.254126.232.127.2551,022
33126.232.128.0/22126.232.128.1 to 126.232.131.254126.232.131.2551,022
34126.232.132.0/22126.232.132.1 to 126.232.135.254126.232.135.2551,022
35126.232.136.0/22126.232.136.1 to 126.232.139.254126.232.139.2551,022
36126.232.140.0/22126.232.140.1 to 126.232.143.254126.232.143.2551,022
37126.232.144.0/22126.232.144.1 to 126.232.147.254126.232.147.2551,022
38126.232.148.0/22126.232.148.1 to 126.232.151.254126.232.151.2551,022
39126.232.152.0/22126.232.152.1 to 126.232.155.254126.232.155.2551,022
40126.232.156.0/22126.232.156.1 to 126.232.159.254126.232.159.2551,022
41126.232.160.0/22126.232.160.1 to 126.232.163.254126.232.163.2551,022
42126.232.164.0/22126.232.164.1 to 126.232.167.254126.232.167.2551,022
43126.232.168.0/22126.232.168.1 to 126.232.171.254126.232.171.2551,022
44126.232.172.0/22126.232.172.1 to 126.232.175.254126.232.175.2551,022
45126.232.176.0/22126.232.176.1 to 126.232.179.254126.232.179.2551,022
46126.232.180.0/22126.232.180.1 to 126.232.183.254126.232.183.2551,022
47126.232.184.0/22126.232.184.1 to 126.232.187.254126.232.187.2551,022
48126.232.188.0/22126.232.188.1 to 126.232.191.254126.232.191.2551,022
49126.232.192.0/22126.232.192.1 to 126.232.195.254126.232.195.2551,022
50126.232.196.0/22126.232.196.1 to 126.232.199.254126.232.199.2551,022
51126.232.200.0/22126.232.200.1 to 126.232.203.254126.232.203.2551,022
52126.232.204.0/22126.232.204.1 to 126.232.207.254126.232.207.2551,022
53126.232.208.0/22126.232.208.1 to 126.232.211.254126.232.211.2551,022
54126.232.212.0/22126.232.212.1 to 126.232.215.254126.232.215.2551,022
55126.232.216.0/22126.232.216.1 to 126.232.219.254126.232.219.2551,022
56126.232.220.0/22126.232.220.1 to 126.232.223.254126.232.223.2551,022
57126.232.224.0/22126.232.224.1 to 126.232.227.254126.232.227.2551,022
58126.232.228.0/22126.232.228.1 to 126.232.231.254126.232.231.2551,022
59126.232.232.0/22126.232.232.1 to 126.232.235.254126.232.235.2551,022
60126.232.236.0/22126.232.236.1 to 126.232.239.254126.232.239.2551,022
61126.232.240.0/22126.232.240.1 to 126.232.243.254126.232.243.2551,022
62126.232.244.0/22126.232.244.1 to 126.232.247.254126.232.247.2551,022
63126.232.248.0/22126.232.248.1 to 126.232.251.254126.232.251.2551,022
64126.232.252.0/22126.232.252.1 to 126.232.255.254126.232.255.2551,022
65126.233.0.0/22126.233.0.1 to 126.233.3.254126.233.3.2551,022
66126.233.4.0/22126.233.4.1 to 126.233.7.254126.233.7.2551,022
67126.233.8.0/22126.233.8.1 to 126.233.11.254126.233.11.2551,022
68126.233.12.0/22126.233.12.1 to 126.233.15.254126.233.15.2551,022
69126.233.16.0/22126.233.16.1 to 126.233.19.254126.233.19.2551,022
70126.233.20.0/22126.233.20.1 to 126.233.23.254126.233.23.2551,022
71126.233.24.0/22126.233.24.1 to 126.233.27.254126.233.27.2551,022
72126.233.28.0/22126.233.28.1 to 126.233.31.254126.233.31.2551,022
73126.233.32.0/22126.233.32.1 to 126.233.35.254126.233.35.2551,022
74126.233.36.0/22126.233.36.1 to 126.233.39.254126.233.39.2551,022
75126.233.40.0/22126.233.40.1 to 126.233.43.254126.233.43.2551,022
76126.233.44.0/22126.233.44.1 to 126.233.47.254126.233.47.2551,022
77126.233.48.0/22126.233.48.1 to 126.233.51.254126.233.51.2551,022
78126.233.52.0/22126.233.52.1 to 126.233.55.254126.233.55.2551,022
79126.233.56.0/22126.233.56.1 to 126.233.59.254126.233.59.2551,022
80126.233.60.0/22126.233.60.1 to 126.233.63.254126.233.63.2551,022
81126.233.64.0/22126.233.64.1 to 126.233.67.254126.233.67.2551,022
82126.233.68.0/22126.233.68.1 to 126.233.71.254126.233.71.2551,022
83126.233.72.0/22126.233.72.1 to 126.233.75.254126.233.75.2551,022
84126.233.76.0/22126.233.76.1 to 126.233.79.254126.233.79.2551,022
85126.233.80.0/22126.233.80.1 to 126.233.83.254126.233.83.2551,022
86126.233.84.0/22126.233.84.1 to 126.233.87.254126.233.87.2551,022
87126.233.88.0/22126.233.88.1 to 126.233.91.254126.233.91.2551,022
88126.233.92.0/22126.233.92.1 to 126.233.95.254126.233.95.2551,022
89126.233.96.0/22126.233.96.1 to 126.233.99.254126.233.99.2551,022
90126.233.100.0/22126.233.100.1 to 126.233.103.254126.233.103.2551,022
91126.233.104.0/22126.233.104.1 to 126.233.107.254126.233.107.2551,022
92126.233.108.0/22126.233.108.1 to 126.233.111.254126.233.111.2551,022
93126.233.112.0/22126.233.112.1 to 126.233.115.254126.233.115.2551,022
94126.233.116.0/22126.233.116.1 to 126.233.119.254126.233.119.2551,022
95126.233.120.0/22126.233.120.1 to 126.233.123.254126.233.123.2551,022
96126.233.124.0/22126.233.124.1 to 126.233.127.254126.233.127.2551,022
97126.233.128.0/22126.233.128.1 to 126.233.131.254126.233.131.2551,022
98126.233.132.0/22126.233.132.1 to 126.233.135.254126.233.135.2551,022
99126.233.136.0/22126.233.136.1 to 126.233.139.254126.233.139.2551,022
100126.233.140.0/22126.233.140.1 to 126.233.143.254126.233.143.2551,022
101126.233.144.0/22126.233.144.1 to 126.233.147.254126.233.147.2551,022
102126.233.148.0/22126.233.148.1 to 126.233.151.254126.233.151.2551,022
103126.233.152.0/22126.233.152.1 to 126.233.155.254126.233.155.2551,022
104126.233.156.0/22126.233.156.1 to 126.233.159.254126.233.159.2551,022
105126.233.160.0/22126.233.160.1 to 126.233.163.254126.233.163.2551,022
106126.233.164.0/22126.233.164.1 to 126.233.167.254126.233.167.2551,022
107126.233.168.0/22126.233.168.1 to 126.233.171.254126.233.171.2551,022
108126.233.172.0/22126.233.172.1 to 126.233.175.254126.233.175.2551,022
109126.233.176.0/22126.233.176.1 to 126.233.179.254126.233.179.2551,022
110126.233.180.0/22126.233.180.1 to 126.233.183.254126.233.183.2551,022
111126.233.184.0/22126.233.184.1 to 126.233.187.254126.233.187.2551,022
112126.233.188.0/22126.233.188.1 to 126.233.191.254126.233.191.2551,022
113126.233.192.0/22126.233.192.1 to 126.233.195.254126.233.195.2551,022
114126.233.196.0/22126.233.196.1 to 126.233.199.254126.233.199.2551,022
115126.233.200.0/22126.233.200.1 to 126.233.203.254126.233.203.2551,022
116126.233.204.0/22126.233.204.1 to 126.233.207.254126.233.207.2551,022
117126.233.208.0/22126.233.208.1 to 126.233.211.254126.233.211.2551,022
118126.233.212.0/22126.233.212.1 to 126.233.215.254126.233.215.2551,022
119126.233.216.0/22126.233.216.1 to 126.233.219.254126.233.219.2551,022
120126.233.220.0/22126.233.220.1 to 126.233.223.254126.233.223.2551,022
121126.233.224.0/22126.233.224.1 to 126.233.227.254126.233.227.2551,022
122126.233.228.0/22126.233.228.1 to 126.233.231.254126.233.231.2551,022
123126.233.232.0/22126.233.232.1 to 126.233.235.254126.233.235.2551,022
124126.233.236.0/22126.233.236.1 to 126.233.239.254126.233.239.2551,022
125126.233.240.0/22126.233.240.1 to 126.233.243.254126.233.243.2551,022
126126.233.244.0/22126.233.244.1 to 126.233.247.254126.233.247.2551,022
127126.233.248.0/22126.233.248.1 to 126.233.251.254126.233.251.2551,022
128126.233.252.0/22126.233.252.1 to 126.233.255.254126.233.255.2551,022
129126.234.0.0/22126.234.0.1 to 126.234.3.254126.234.3.2551,022
130126.234.4.0/22126.234.4.1 to 126.234.7.254126.234.7.2551,022
131126.234.8.0/22126.234.8.1 to 126.234.11.254126.234.11.2551,022
132126.234.12.0/22126.234.12.1 to 126.234.15.254126.234.15.2551,022
133126.234.16.0/22126.234.16.1 to 126.234.19.254126.234.19.2551,022
134126.234.20.0/22126.234.20.1 to 126.234.23.254126.234.23.2551,022
135126.234.24.0/22126.234.24.1 to 126.234.27.254126.234.27.2551,022
136126.234.28.0/22126.234.28.1 to 126.234.31.254126.234.31.2551,022
137126.234.32.0/22126.234.32.1 to 126.234.35.254126.234.35.2551,022
138126.234.36.0/22126.234.36.1 to 126.234.39.254126.234.39.2551,022
139126.234.40.0/22126.234.40.1 to 126.234.43.254126.234.43.2551,022
140126.234.44.0/22126.234.44.1 to 126.234.47.254126.234.47.2551,022
141126.234.48.0/22126.234.48.1 to 126.234.51.254126.234.51.2551,022
142126.234.52.0/22126.234.52.1 to 126.234.55.254126.234.55.2551,022
143126.234.56.0/22126.234.56.1 to 126.234.59.254126.234.59.2551,022
144126.234.60.0/22126.234.60.1 to 126.234.63.254126.234.63.2551,022
145126.234.64.0/22126.234.64.1 to 126.234.67.254126.234.67.2551,022
146126.234.68.0/22126.234.68.1 to 126.234.71.254126.234.71.2551,022
147126.234.72.0/22126.234.72.1 to 126.234.75.254126.234.75.2551,022
148126.234.76.0/22126.234.76.1 to 126.234.79.254126.234.79.2551,022
149126.234.80.0/22126.234.80.1 to 126.234.83.254126.234.83.2551,022
150126.234.84.0/22126.234.84.1 to 126.234.87.254126.234.87.2551,022
151126.234.88.0/22126.234.88.1 to 126.234.91.254126.234.91.2551,022
152126.234.92.0/22126.234.92.1 to 126.234.95.254126.234.95.2551,022
153126.234.96.0/22126.234.96.1 to 126.234.99.254126.234.99.2551,022
154126.234.100.0/22126.234.100.1 to 126.234.103.254126.234.103.2551,022
155126.234.104.0/22126.234.104.1 to 126.234.107.254126.234.107.2551,022
156126.234.108.0/22126.234.108.1 to 126.234.111.254126.234.111.2551,022
157126.234.112.0/22126.234.112.1 to 126.234.115.254126.234.115.2551,022
158126.234.116.0/22126.234.116.1 to 126.234.119.254126.234.119.2551,022
159126.234.120.0/22126.234.120.1 to 126.234.123.254126.234.123.2551,022
160126.234.124.0/22126.234.124.1 to 126.234.127.254126.234.127.2551,022
161126.234.128.0/22126.234.128.1 to 126.234.131.254126.234.131.2551,022
162126.234.132.0/22126.234.132.1 to 126.234.135.254126.234.135.2551,022
163126.234.136.0/22126.234.136.1 to 126.234.139.254126.234.139.2551,022
164126.234.140.0/22126.234.140.1 to 126.234.143.254126.234.143.2551,022
165126.234.144.0/22126.234.144.1 to 126.234.147.254126.234.147.2551,022
166126.234.148.0/22126.234.148.1 to 126.234.151.254126.234.151.2551,022
167126.234.152.0/22126.234.152.1 to 126.234.155.254126.234.155.2551,022
168126.234.156.0/22126.234.156.1 to 126.234.159.254126.234.159.2551,022
169126.234.160.0/22126.234.160.1 to 126.234.163.254126.234.163.2551,022
170126.234.164.0/22126.234.164.1 to 126.234.167.254126.234.167.2551,022
171126.234.168.0/22126.234.168.1 to 126.234.171.254126.234.171.2551,022
172126.234.172.0/22126.234.172.1 to 126.234.175.254126.234.175.2551,022
173126.234.176.0/22126.234.176.1 to 126.234.179.254126.234.179.2551,022
174126.234.180.0/22126.234.180.1 to 126.234.183.254126.234.183.2551,022
175126.234.184.0/22126.234.184.1 to 126.234.187.254126.234.187.2551,022
176126.234.188.0/22126.234.188.1 to 126.234.191.254126.234.191.2551,022
177126.234.192.0/22126.234.192.1 to 126.234.195.254126.234.195.2551,022
178126.234.196.0/22126.234.196.1 to 126.234.199.254126.234.199.2551,022
179126.234.200.0/22126.234.200.1 to 126.234.203.254126.234.203.2551,022
180126.234.204.0/22126.234.204.1 to 126.234.207.254126.234.207.2551,022
181126.234.208.0/22126.234.208.1 to 126.234.211.254126.234.211.2551,022
182126.234.212.0/22126.234.212.1 to 126.234.215.254126.234.215.2551,022
183126.234.216.0/22126.234.216.1 to 126.234.219.254126.234.219.2551,022
184126.234.220.0/22126.234.220.1 to 126.234.223.254126.234.223.2551,022
185126.234.224.0/22126.234.224.1 to 126.234.227.254126.234.227.2551,022
186126.234.228.0/22126.234.228.1 to 126.234.231.254126.234.231.2551,022
187126.234.232.0/22126.234.232.1 to 126.234.235.254126.234.235.2551,022
188126.234.236.0/22126.234.236.1 to 126.234.239.254126.234.239.2551,022
189126.234.240.0/22126.234.240.1 to 126.234.243.254126.234.243.2551,022
190126.234.244.0/22126.234.244.1 to 126.234.247.254126.234.247.2551,022
191126.234.248.0/22126.234.248.1 to 126.234.251.254126.234.251.2551,022
192126.234.252.0/22126.234.252.1 to 126.234.255.254126.234.255.2551,022
193126.235.0.0/22126.235.0.1 to 126.235.3.254126.235.3.2551,022
194126.235.4.0/22126.235.4.1 to 126.235.7.254126.235.7.2551,022
195126.235.8.0/22126.235.8.1 to 126.235.11.254126.235.11.2551,022
196126.235.12.0/22126.235.12.1 to 126.235.15.254126.235.15.2551,022
197126.235.16.0/22126.235.16.1 to 126.235.19.254126.235.19.2551,022
198126.235.20.0/22126.235.20.1 to 126.235.23.254126.235.23.2551,022
199126.235.24.0/22126.235.24.1 to 126.235.27.254126.235.27.2551,022
200126.235.28.0/22126.235.28.1 to 126.235.31.254126.235.31.2551,022
201126.235.32.0/22126.235.32.1 to 126.235.35.254126.235.35.2551,022
202126.235.36.0/22126.235.36.1 to 126.235.39.254126.235.39.2551,022
203126.235.40.0/22126.235.40.1 to 126.235.43.254126.235.43.2551,022
204126.235.44.0/22126.235.44.1 to 126.235.47.254126.235.47.2551,022
205126.235.48.0/22126.235.48.1 to 126.235.51.254126.235.51.2551,022
206126.235.52.0/22126.235.52.1 to 126.235.55.254126.235.55.2551,022
207126.235.56.0/22126.235.56.1 to 126.235.59.254126.235.59.2551,022
208126.235.60.0/22126.235.60.1 to 126.235.63.254126.235.63.2551,022
209126.235.64.0/22126.235.64.1 to 126.235.67.254126.235.67.2551,022
210126.235.68.0/22126.235.68.1 to 126.235.71.254126.235.71.2551,022
211126.235.72.0/22126.235.72.1 to 126.235.75.254126.235.75.2551,022
212126.235.76.0/22126.235.76.1 to 126.235.79.254126.235.79.2551,022
213126.235.80.0/22126.235.80.1 to 126.235.83.254126.235.83.2551,022
214126.235.84.0/22126.235.84.1 to 126.235.87.254126.235.87.2551,022
215126.235.88.0/22126.235.88.1 to 126.235.91.254126.235.91.2551,022
216126.235.92.0/22126.235.92.1 to 126.235.95.254126.235.95.2551,022
217126.235.96.0/22126.235.96.1 to 126.235.99.254126.235.99.2551,022
218126.235.100.0/22126.235.100.1 to 126.235.103.254126.235.103.2551,022
219126.235.104.0/22126.235.104.1 to 126.235.107.254126.235.107.2551,022
220126.235.108.0/22126.235.108.1 to 126.235.111.254126.235.111.2551,022
221126.235.112.0/22126.235.112.1 to 126.235.115.254126.235.115.2551,022
222126.235.116.0/22126.235.116.1 to 126.235.119.254126.235.119.2551,022
223126.235.120.0/22126.235.120.1 to 126.235.123.254126.235.123.2551,022
224126.235.124.0/22126.235.124.1 to 126.235.127.254126.235.127.2551,022
225126.235.128.0/22126.235.128.1 to 126.235.131.254126.235.131.2551,022
226126.235.132.0/22126.235.132.1 to 126.235.135.254126.235.135.2551,022
227126.235.136.0/22126.235.136.1 to 126.235.139.254126.235.139.2551,022
228126.235.140.0/22126.235.140.1 to 126.235.143.254126.235.143.2551,022
229126.235.144.0/22126.235.144.1 to 126.235.147.254126.235.147.2551,022
230126.235.148.0/22126.235.148.1 to 126.235.151.254126.235.151.2551,022
231126.235.152.0/22126.235.152.1 to 126.235.155.254126.235.155.2551,022
232126.235.156.0/22126.235.156.1 to 126.235.159.254126.235.159.2551,022
233126.235.160.0/22126.235.160.1 to 126.235.163.254126.235.163.2551,022
234126.235.164.0/22126.235.164.1 to 126.235.167.254126.235.167.2551,022
235126.235.168.0/22126.235.168.1 to 126.235.171.254126.235.171.2551,022
236126.235.172.0/22126.235.172.1 to 126.235.175.254126.235.175.2551,022
237126.235.176.0/22126.235.176.1 to 126.235.179.254126.235.179.2551,022
238126.235.180.0/22126.235.180.1 to 126.235.183.254126.235.183.2551,022
239126.235.184.0/22126.235.184.1 to 126.235.187.254126.235.187.2551,022
240126.235.188.0/22126.235.188.1 to 126.235.191.254126.235.191.2551,022
241126.235.192.0/22126.235.192.1 to 126.235.195.254126.235.195.2551,022
242126.235.196.0/22126.235.196.1 to 126.235.199.254126.235.199.2551,022
243126.235.200.0/22126.235.200.1 to 126.235.203.254126.235.203.2551,022
244126.235.204.0/22126.235.204.1 to 126.235.207.254126.235.207.2551,022
245126.235.208.0/22126.235.208.1 to 126.235.211.254126.235.211.2551,022
246126.235.212.0/22126.235.212.1 to 126.235.215.254126.235.215.2551,022
247126.235.216.0/22126.235.216.1 to 126.235.219.254126.235.219.2551,022
248126.235.220.0/22126.235.220.1 to 126.235.223.254126.235.223.2551,022
249126.235.224.0/22126.235.224.1 to 126.235.227.254126.235.227.2551,022
250126.235.228.0/22126.235.228.1 to 126.235.231.254126.235.231.2551,022
251126.235.232.0/22126.235.232.1 to 126.235.235.254126.235.235.2551,022
252126.235.236.0/22126.235.236.1 to 126.235.239.254126.235.239.2551,022
253126.235.240.0/22126.235.240.1 to 126.235.243.254126.235.243.2551,022
254126.235.244.0/22126.235.244.1 to 126.235.247.254126.235.247.2551,022
255126.235.248.0/22126.235.248.1 to 126.235.251.254126.235.251.2551,022
256126.235.252.0/22126.235.252.1 to 126.235.255.254126.235.255.2551,022

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.