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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.

Network115.0.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
115.0.0.0
Broadcast address
115.31.255.255
First usable
115.0.0.1
Last usable
115.31.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 73000000 · Integer 1929379840 to 1931476991
Reverse DNS zones
0.115.in-addr.arpa
1.115.in-addr.arpa
2.115.in-addr.arpa
3.115.in-addr.arpa
4.115.in-addr.arpa
5.115.in-addr.arpa
6.115.in-addr.arpa
7.115.in-addr.arpa
8.115.in-addr.arpa
9.115.in-addr.arpa
10.115.in-addr.arpa
11.115.in-addr.arpa
12.115.in-addr.arpa
13.115.in-addr.arpa
14.115.in-addr.arpa
15.115.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110011.00000000.00000000.00000000115.0.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network01110011.00000000.00000000.00000000115.0.0.0
Broadcast01110011.00011111.11111111.11111111115.31.255.255
Split into smaller subnets/22
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

115.0.0.0/11 makes 2,048 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1115.0.0.0/22115.0.0.1 to 115.0.3.254115.0.3.2551,022
2115.0.4.0/22115.0.4.1 to 115.0.7.254115.0.7.2551,022
3115.0.8.0/22115.0.8.1 to 115.0.11.254115.0.11.2551,022
4115.0.12.0/22115.0.12.1 to 115.0.15.254115.0.15.2551,022
5115.0.16.0/22115.0.16.1 to 115.0.19.254115.0.19.2551,022
6115.0.20.0/22115.0.20.1 to 115.0.23.254115.0.23.2551,022
7115.0.24.0/22115.0.24.1 to 115.0.27.254115.0.27.2551,022
8115.0.28.0/22115.0.28.1 to 115.0.31.254115.0.31.2551,022
9115.0.32.0/22115.0.32.1 to 115.0.35.254115.0.35.2551,022
10115.0.36.0/22115.0.36.1 to 115.0.39.254115.0.39.2551,022
11115.0.40.0/22115.0.40.1 to 115.0.43.254115.0.43.2551,022
12115.0.44.0/22115.0.44.1 to 115.0.47.254115.0.47.2551,022
13115.0.48.0/22115.0.48.1 to 115.0.51.254115.0.51.2551,022
14115.0.52.0/22115.0.52.1 to 115.0.55.254115.0.55.2551,022
15115.0.56.0/22115.0.56.1 to 115.0.59.254115.0.59.2551,022
16115.0.60.0/22115.0.60.1 to 115.0.63.254115.0.63.2551,022
17115.0.64.0/22115.0.64.1 to 115.0.67.254115.0.67.2551,022
18115.0.68.0/22115.0.68.1 to 115.0.71.254115.0.71.2551,022
19115.0.72.0/22115.0.72.1 to 115.0.75.254115.0.75.2551,022
20115.0.76.0/22115.0.76.1 to 115.0.79.254115.0.79.2551,022
21115.0.80.0/22115.0.80.1 to 115.0.83.254115.0.83.2551,022
22115.0.84.0/22115.0.84.1 to 115.0.87.254115.0.87.2551,022
23115.0.88.0/22115.0.88.1 to 115.0.91.254115.0.91.2551,022
24115.0.92.0/22115.0.92.1 to 115.0.95.254115.0.95.2551,022
25115.0.96.0/22115.0.96.1 to 115.0.99.254115.0.99.2551,022
26115.0.100.0/22115.0.100.1 to 115.0.103.254115.0.103.2551,022
27115.0.104.0/22115.0.104.1 to 115.0.107.254115.0.107.2551,022
28115.0.108.0/22115.0.108.1 to 115.0.111.254115.0.111.2551,022
29115.0.112.0/22115.0.112.1 to 115.0.115.254115.0.115.2551,022
30115.0.116.0/22115.0.116.1 to 115.0.119.254115.0.119.2551,022
31115.0.120.0/22115.0.120.1 to 115.0.123.254115.0.123.2551,022
32115.0.124.0/22115.0.124.1 to 115.0.127.254115.0.127.2551,022
33115.0.128.0/22115.0.128.1 to 115.0.131.254115.0.131.2551,022
34115.0.132.0/22115.0.132.1 to 115.0.135.254115.0.135.2551,022
35115.0.136.0/22115.0.136.1 to 115.0.139.254115.0.139.2551,022
36115.0.140.0/22115.0.140.1 to 115.0.143.254115.0.143.2551,022
37115.0.144.0/22115.0.144.1 to 115.0.147.254115.0.147.2551,022
38115.0.148.0/22115.0.148.1 to 115.0.151.254115.0.151.2551,022
39115.0.152.0/22115.0.152.1 to 115.0.155.254115.0.155.2551,022
40115.0.156.0/22115.0.156.1 to 115.0.159.254115.0.159.2551,022
41115.0.160.0/22115.0.160.1 to 115.0.163.254115.0.163.2551,022
42115.0.164.0/22115.0.164.1 to 115.0.167.254115.0.167.2551,022
43115.0.168.0/22115.0.168.1 to 115.0.171.254115.0.171.2551,022
44115.0.172.0/22115.0.172.1 to 115.0.175.254115.0.175.2551,022
45115.0.176.0/22115.0.176.1 to 115.0.179.254115.0.179.2551,022
46115.0.180.0/22115.0.180.1 to 115.0.183.254115.0.183.2551,022
47115.0.184.0/22115.0.184.1 to 115.0.187.254115.0.187.2551,022
48115.0.188.0/22115.0.188.1 to 115.0.191.254115.0.191.2551,022
49115.0.192.0/22115.0.192.1 to 115.0.195.254115.0.195.2551,022
50115.0.196.0/22115.0.196.1 to 115.0.199.254115.0.199.2551,022
51115.0.200.0/22115.0.200.1 to 115.0.203.254115.0.203.2551,022
52115.0.204.0/22115.0.204.1 to 115.0.207.254115.0.207.2551,022
53115.0.208.0/22115.0.208.1 to 115.0.211.254115.0.211.2551,022
54115.0.212.0/22115.0.212.1 to 115.0.215.254115.0.215.2551,022
55115.0.216.0/22115.0.216.1 to 115.0.219.254115.0.219.2551,022
56115.0.220.0/22115.0.220.1 to 115.0.223.254115.0.223.2551,022
57115.0.224.0/22115.0.224.1 to 115.0.227.254115.0.227.2551,022
58115.0.228.0/22115.0.228.1 to 115.0.231.254115.0.231.2551,022
59115.0.232.0/22115.0.232.1 to 115.0.235.254115.0.235.2551,022
60115.0.236.0/22115.0.236.1 to 115.0.239.254115.0.239.2551,022
61115.0.240.0/22115.0.240.1 to 115.0.243.254115.0.243.2551,022
62115.0.244.0/22115.0.244.1 to 115.0.247.254115.0.247.2551,022
63115.0.248.0/22115.0.248.1 to 115.0.251.254115.0.251.2551,022
64115.0.252.0/22115.0.252.1 to 115.0.255.254115.0.255.2551,022
65115.1.0.0/22115.1.0.1 to 115.1.3.254115.1.3.2551,022
66115.1.4.0/22115.1.4.1 to 115.1.7.254115.1.7.2551,022
67115.1.8.0/22115.1.8.1 to 115.1.11.254115.1.11.2551,022
68115.1.12.0/22115.1.12.1 to 115.1.15.254115.1.15.2551,022
69115.1.16.0/22115.1.16.1 to 115.1.19.254115.1.19.2551,022
70115.1.20.0/22115.1.20.1 to 115.1.23.254115.1.23.2551,022
71115.1.24.0/22115.1.24.1 to 115.1.27.254115.1.27.2551,022
72115.1.28.0/22115.1.28.1 to 115.1.31.254115.1.31.2551,022
73115.1.32.0/22115.1.32.1 to 115.1.35.254115.1.35.2551,022
74115.1.36.0/22115.1.36.1 to 115.1.39.254115.1.39.2551,022
75115.1.40.0/22115.1.40.1 to 115.1.43.254115.1.43.2551,022
76115.1.44.0/22115.1.44.1 to 115.1.47.254115.1.47.2551,022
77115.1.48.0/22115.1.48.1 to 115.1.51.254115.1.51.2551,022
78115.1.52.0/22115.1.52.1 to 115.1.55.254115.1.55.2551,022
79115.1.56.0/22115.1.56.1 to 115.1.59.254115.1.59.2551,022
80115.1.60.0/22115.1.60.1 to 115.1.63.254115.1.63.2551,022
81115.1.64.0/22115.1.64.1 to 115.1.67.254115.1.67.2551,022
82115.1.68.0/22115.1.68.1 to 115.1.71.254115.1.71.2551,022
83115.1.72.0/22115.1.72.1 to 115.1.75.254115.1.75.2551,022
84115.1.76.0/22115.1.76.1 to 115.1.79.254115.1.79.2551,022
85115.1.80.0/22115.1.80.1 to 115.1.83.254115.1.83.2551,022
86115.1.84.0/22115.1.84.1 to 115.1.87.254115.1.87.2551,022
87115.1.88.0/22115.1.88.1 to 115.1.91.254115.1.91.2551,022
88115.1.92.0/22115.1.92.1 to 115.1.95.254115.1.95.2551,022
89115.1.96.0/22115.1.96.1 to 115.1.99.254115.1.99.2551,022
90115.1.100.0/22115.1.100.1 to 115.1.103.254115.1.103.2551,022
91115.1.104.0/22115.1.104.1 to 115.1.107.254115.1.107.2551,022
92115.1.108.0/22115.1.108.1 to 115.1.111.254115.1.111.2551,022
93115.1.112.0/22115.1.112.1 to 115.1.115.254115.1.115.2551,022
94115.1.116.0/22115.1.116.1 to 115.1.119.254115.1.119.2551,022
95115.1.120.0/22115.1.120.1 to 115.1.123.254115.1.123.2551,022
96115.1.124.0/22115.1.124.1 to 115.1.127.254115.1.127.2551,022
97115.1.128.0/22115.1.128.1 to 115.1.131.254115.1.131.2551,022
98115.1.132.0/22115.1.132.1 to 115.1.135.254115.1.135.2551,022
99115.1.136.0/22115.1.136.1 to 115.1.139.254115.1.139.2551,022
100115.1.140.0/22115.1.140.1 to 115.1.143.254115.1.143.2551,022
101115.1.144.0/22115.1.144.1 to 115.1.147.254115.1.147.2551,022
102115.1.148.0/22115.1.148.1 to 115.1.151.254115.1.151.2551,022
103115.1.152.0/22115.1.152.1 to 115.1.155.254115.1.155.2551,022
104115.1.156.0/22115.1.156.1 to 115.1.159.254115.1.159.2551,022
105115.1.160.0/22115.1.160.1 to 115.1.163.254115.1.163.2551,022
106115.1.164.0/22115.1.164.1 to 115.1.167.254115.1.167.2551,022
107115.1.168.0/22115.1.168.1 to 115.1.171.254115.1.171.2551,022
108115.1.172.0/22115.1.172.1 to 115.1.175.254115.1.175.2551,022
109115.1.176.0/22115.1.176.1 to 115.1.179.254115.1.179.2551,022
110115.1.180.0/22115.1.180.1 to 115.1.183.254115.1.183.2551,022
111115.1.184.0/22115.1.184.1 to 115.1.187.254115.1.187.2551,022
112115.1.188.0/22115.1.188.1 to 115.1.191.254115.1.191.2551,022
113115.1.192.0/22115.1.192.1 to 115.1.195.254115.1.195.2551,022
114115.1.196.0/22115.1.196.1 to 115.1.199.254115.1.199.2551,022
115115.1.200.0/22115.1.200.1 to 115.1.203.254115.1.203.2551,022
116115.1.204.0/22115.1.204.1 to 115.1.207.254115.1.207.2551,022
117115.1.208.0/22115.1.208.1 to 115.1.211.254115.1.211.2551,022
118115.1.212.0/22115.1.212.1 to 115.1.215.254115.1.215.2551,022
119115.1.216.0/22115.1.216.1 to 115.1.219.254115.1.219.2551,022
120115.1.220.0/22115.1.220.1 to 115.1.223.254115.1.223.2551,022
121115.1.224.0/22115.1.224.1 to 115.1.227.254115.1.227.2551,022
122115.1.228.0/22115.1.228.1 to 115.1.231.254115.1.231.2551,022
123115.1.232.0/22115.1.232.1 to 115.1.235.254115.1.235.2551,022
124115.1.236.0/22115.1.236.1 to 115.1.239.254115.1.239.2551,022
125115.1.240.0/22115.1.240.1 to 115.1.243.254115.1.243.2551,022
126115.1.244.0/22115.1.244.1 to 115.1.247.254115.1.247.2551,022
127115.1.248.0/22115.1.248.1 to 115.1.251.254115.1.251.2551,022
128115.1.252.0/22115.1.252.1 to 115.1.255.254115.1.255.2551,022
129115.2.0.0/22115.2.0.1 to 115.2.3.254115.2.3.2551,022
130115.2.4.0/22115.2.4.1 to 115.2.7.254115.2.7.2551,022
131115.2.8.0/22115.2.8.1 to 115.2.11.254115.2.11.2551,022
132115.2.12.0/22115.2.12.1 to 115.2.15.254115.2.15.2551,022
133115.2.16.0/22115.2.16.1 to 115.2.19.254115.2.19.2551,022
134115.2.20.0/22115.2.20.1 to 115.2.23.254115.2.23.2551,022
135115.2.24.0/22115.2.24.1 to 115.2.27.254115.2.27.2551,022
136115.2.28.0/22115.2.28.1 to 115.2.31.254115.2.31.2551,022
137115.2.32.0/22115.2.32.1 to 115.2.35.254115.2.35.2551,022
138115.2.36.0/22115.2.36.1 to 115.2.39.254115.2.39.2551,022
139115.2.40.0/22115.2.40.1 to 115.2.43.254115.2.43.2551,022
140115.2.44.0/22115.2.44.1 to 115.2.47.254115.2.47.2551,022
141115.2.48.0/22115.2.48.1 to 115.2.51.254115.2.51.2551,022
142115.2.52.0/22115.2.52.1 to 115.2.55.254115.2.55.2551,022
143115.2.56.0/22115.2.56.1 to 115.2.59.254115.2.59.2551,022
144115.2.60.0/22115.2.60.1 to 115.2.63.254115.2.63.2551,022
145115.2.64.0/22115.2.64.1 to 115.2.67.254115.2.67.2551,022
146115.2.68.0/22115.2.68.1 to 115.2.71.254115.2.71.2551,022
147115.2.72.0/22115.2.72.1 to 115.2.75.254115.2.75.2551,022
148115.2.76.0/22115.2.76.1 to 115.2.79.254115.2.79.2551,022
149115.2.80.0/22115.2.80.1 to 115.2.83.254115.2.83.2551,022
150115.2.84.0/22115.2.84.1 to 115.2.87.254115.2.87.2551,022
151115.2.88.0/22115.2.88.1 to 115.2.91.254115.2.91.2551,022
152115.2.92.0/22115.2.92.1 to 115.2.95.254115.2.95.2551,022
153115.2.96.0/22115.2.96.1 to 115.2.99.254115.2.99.2551,022
154115.2.100.0/22115.2.100.1 to 115.2.103.254115.2.103.2551,022
155115.2.104.0/22115.2.104.1 to 115.2.107.254115.2.107.2551,022
156115.2.108.0/22115.2.108.1 to 115.2.111.254115.2.111.2551,022
157115.2.112.0/22115.2.112.1 to 115.2.115.254115.2.115.2551,022
158115.2.116.0/22115.2.116.1 to 115.2.119.254115.2.119.2551,022
159115.2.120.0/22115.2.120.1 to 115.2.123.254115.2.123.2551,022
160115.2.124.0/22115.2.124.1 to 115.2.127.254115.2.127.2551,022
161115.2.128.0/22115.2.128.1 to 115.2.131.254115.2.131.2551,022
162115.2.132.0/22115.2.132.1 to 115.2.135.254115.2.135.2551,022
163115.2.136.0/22115.2.136.1 to 115.2.139.254115.2.139.2551,022
164115.2.140.0/22115.2.140.1 to 115.2.143.254115.2.143.2551,022
165115.2.144.0/22115.2.144.1 to 115.2.147.254115.2.147.2551,022
166115.2.148.0/22115.2.148.1 to 115.2.151.254115.2.151.2551,022
167115.2.152.0/22115.2.152.1 to 115.2.155.254115.2.155.2551,022
168115.2.156.0/22115.2.156.1 to 115.2.159.254115.2.159.2551,022
169115.2.160.0/22115.2.160.1 to 115.2.163.254115.2.163.2551,022
170115.2.164.0/22115.2.164.1 to 115.2.167.254115.2.167.2551,022
171115.2.168.0/22115.2.168.1 to 115.2.171.254115.2.171.2551,022
172115.2.172.0/22115.2.172.1 to 115.2.175.254115.2.175.2551,022
173115.2.176.0/22115.2.176.1 to 115.2.179.254115.2.179.2551,022
174115.2.180.0/22115.2.180.1 to 115.2.183.254115.2.183.2551,022
175115.2.184.0/22115.2.184.1 to 115.2.187.254115.2.187.2551,022
176115.2.188.0/22115.2.188.1 to 115.2.191.254115.2.191.2551,022
177115.2.192.0/22115.2.192.1 to 115.2.195.254115.2.195.2551,022
178115.2.196.0/22115.2.196.1 to 115.2.199.254115.2.199.2551,022
179115.2.200.0/22115.2.200.1 to 115.2.203.254115.2.203.2551,022
180115.2.204.0/22115.2.204.1 to 115.2.207.254115.2.207.2551,022
181115.2.208.0/22115.2.208.1 to 115.2.211.254115.2.211.2551,022
182115.2.212.0/22115.2.212.1 to 115.2.215.254115.2.215.2551,022
183115.2.216.0/22115.2.216.1 to 115.2.219.254115.2.219.2551,022
184115.2.220.0/22115.2.220.1 to 115.2.223.254115.2.223.2551,022
185115.2.224.0/22115.2.224.1 to 115.2.227.254115.2.227.2551,022
186115.2.228.0/22115.2.228.1 to 115.2.231.254115.2.231.2551,022
187115.2.232.0/22115.2.232.1 to 115.2.235.254115.2.235.2551,022
188115.2.236.0/22115.2.236.1 to 115.2.239.254115.2.239.2551,022
189115.2.240.0/22115.2.240.1 to 115.2.243.254115.2.243.2551,022
190115.2.244.0/22115.2.244.1 to 115.2.247.254115.2.247.2551,022
191115.2.248.0/22115.2.248.1 to 115.2.251.254115.2.251.2551,022
192115.2.252.0/22115.2.252.1 to 115.2.255.254115.2.255.2551,022
193115.3.0.0/22115.3.0.1 to 115.3.3.254115.3.3.2551,022
194115.3.4.0/22115.3.4.1 to 115.3.7.254115.3.7.2551,022
195115.3.8.0/22115.3.8.1 to 115.3.11.254115.3.11.2551,022
196115.3.12.0/22115.3.12.1 to 115.3.15.254115.3.15.2551,022
197115.3.16.0/22115.3.16.1 to 115.3.19.254115.3.19.2551,022
198115.3.20.0/22115.3.20.1 to 115.3.23.254115.3.23.2551,022
199115.3.24.0/22115.3.24.1 to 115.3.27.254115.3.27.2551,022
200115.3.28.0/22115.3.28.1 to 115.3.31.254115.3.31.2551,022
201115.3.32.0/22115.3.32.1 to 115.3.35.254115.3.35.2551,022
202115.3.36.0/22115.3.36.1 to 115.3.39.254115.3.39.2551,022
203115.3.40.0/22115.3.40.1 to 115.3.43.254115.3.43.2551,022
204115.3.44.0/22115.3.44.1 to 115.3.47.254115.3.47.2551,022
205115.3.48.0/22115.3.48.1 to 115.3.51.254115.3.51.2551,022
206115.3.52.0/22115.3.52.1 to 115.3.55.254115.3.55.2551,022
207115.3.56.0/22115.3.56.1 to 115.3.59.254115.3.59.2551,022
208115.3.60.0/22115.3.60.1 to 115.3.63.254115.3.63.2551,022
209115.3.64.0/22115.3.64.1 to 115.3.67.254115.3.67.2551,022
210115.3.68.0/22115.3.68.1 to 115.3.71.254115.3.71.2551,022
211115.3.72.0/22115.3.72.1 to 115.3.75.254115.3.75.2551,022
212115.3.76.0/22115.3.76.1 to 115.3.79.254115.3.79.2551,022
213115.3.80.0/22115.3.80.1 to 115.3.83.254115.3.83.2551,022
214115.3.84.0/22115.3.84.1 to 115.3.87.254115.3.87.2551,022
215115.3.88.0/22115.3.88.1 to 115.3.91.254115.3.91.2551,022
216115.3.92.0/22115.3.92.1 to 115.3.95.254115.3.95.2551,022
217115.3.96.0/22115.3.96.1 to 115.3.99.254115.3.99.2551,022
218115.3.100.0/22115.3.100.1 to 115.3.103.254115.3.103.2551,022
219115.3.104.0/22115.3.104.1 to 115.3.107.254115.3.107.2551,022
220115.3.108.0/22115.3.108.1 to 115.3.111.254115.3.111.2551,022
221115.3.112.0/22115.3.112.1 to 115.3.115.254115.3.115.2551,022
222115.3.116.0/22115.3.116.1 to 115.3.119.254115.3.119.2551,022
223115.3.120.0/22115.3.120.1 to 115.3.123.254115.3.123.2551,022
224115.3.124.0/22115.3.124.1 to 115.3.127.254115.3.127.2551,022
225115.3.128.0/22115.3.128.1 to 115.3.131.254115.3.131.2551,022
226115.3.132.0/22115.3.132.1 to 115.3.135.254115.3.135.2551,022
227115.3.136.0/22115.3.136.1 to 115.3.139.254115.3.139.2551,022
228115.3.140.0/22115.3.140.1 to 115.3.143.254115.3.143.2551,022
229115.3.144.0/22115.3.144.1 to 115.3.147.254115.3.147.2551,022
230115.3.148.0/22115.3.148.1 to 115.3.151.254115.3.151.2551,022
231115.3.152.0/22115.3.152.1 to 115.3.155.254115.3.155.2551,022
232115.3.156.0/22115.3.156.1 to 115.3.159.254115.3.159.2551,022
233115.3.160.0/22115.3.160.1 to 115.3.163.254115.3.163.2551,022
234115.3.164.0/22115.3.164.1 to 115.3.167.254115.3.167.2551,022
235115.3.168.0/22115.3.168.1 to 115.3.171.254115.3.171.2551,022
236115.3.172.0/22115.3.172.1 to 115.3.175.254115.3.175.2551,022
237115.3.176.0/22115.3.176.1 to 115.3.179.254115.3.179.2551,022
238115.3.180.0/22115.3.180.1 to 115.3.183.254115.3.183.2551,022
239115.3.184.0/22115.3.184.1 to 115.3.187.254115.3.187.2551,022
240115.3.188.0/22115.3.188.1 to 115.3.191.254115.3.191.2551,022
241115.3.192.0/22115.3.192.1 to 115.3.195.254115.3.195.2551,022
242115.3.196.0/22115.3.196.1 to 115.3.199.254115.3.199.2551,022
243115.3.200.0/22115.3.200.1 to 115.3.203.254115.3.203.2551,022
244115.3.204.0/22115.3.204.1 to 115.3.207.254115.3.207.2551,022
245115.3.208.0/22115.3.208.1 to 115.3.211.254115.3.211.2551,022
246115.3.212.0/22115.3.212.1 to 115.3.215.254115.3.215.2551,022
247115.3.216.0/22115.3.216.1 to 115.3.219.254115.3.219.2551,022
248115.3.220.0/22115.3.220.1 to 115.3.223.254115.3.223.2551,022
249115.3.224.0/22115.3.224.1 to 115.3.227.254115.3.227.2551,022
250115.3.228.0/22115.3.228.1 to 115.3.231.254115.3.231.2551,022
251115.3.232.0/22115.3.232.1 to 115.3.235.254115.3.235.2551,022
252115.3.236.0/22115.3.236.1 to 115.3.239.254115.3.239.2551,022
253115.3.240.0/22115.3.240.1 to 115.3.243.254115.3.243.2551,022
254115.3.244.0/22115.3.244.1 to 115.3.247.254115.3.247.2551,022
255115.3.248.0/22115.3.248.1 to 115.3.251.254115.3.251.2551,022
256115.3.252.0/22115.3.252.1 to 115.3.255.254115.3.255.2551,022

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.