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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.

Network180.136.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
180.136.0.0
Broadcast address
180.139.255.255
First usable
180.136.0.1
Last usable
180.139.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex B4880000 · Integer 3028811776 to 3029073919
Reverse DNS zones
136.180.in-addr.arpa
137.180.in-addr.arpa
138.180.in-addr.arpa
139.180.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10110100.10001000.00000000.00000000180.136.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10110100.10001000.00000000.00000000180.136.0.0
Broadcast10110100.10001011.11111111.11111111180.139.255.255
Split into smaller subnets/22
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

180.136.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1180.136.0.0/22180.136.0.1 to 180.136.3.254180.136.3.2551,022
2180.136.4.0/22180.136.4.1 to 180.136.7.254180.136.7.2551,022
3180.136.8.0/22180.136.8.1 to 180.136.11.254180.136.11.2551,022
4180.136.12.0/22180.136.12.1 to 180.136.15.254180.136.15.2551,022
5180.136.16.0/22180.136.16.1 to 180.136.19.254180.136.19.2551,022
6180.136.20.0/22180.136.20.1 to 180.136.23.254180.136.23.2551,022
7180.136.24.0/22180.136.24.1 to 180.136.27.254180.136.27.2551,022
8180.136.28.0/22180.136.28.1 to 180.136.31.254180.136.31.2551,022
9180.136.32.0/22180.136.32.1 to 180.136.35.254180.136.35.2551,022
10180.136.36.0/22180.136.36.1 to 180.136.39.254180.136.39.2551,022
11180.136.40.0/22180.136.40.1 to 180.136.43.254180.136.43.2551,022
12180.136.44.0/22180.136.44.1 to 180.136.47.254180.136.47.2551,022
13180.136.48.0/22180.136.48.1 to 180.136.51.254180.136.51.2551,022
14180.136.52.0/22180.136.52.1 to 180.136.55.254180.136.55.2551,022
15180.136.56.0/22180.136.56.1 to 180.136.59.254180.136.59.2551,022
16180.136.60.0/22180.136.60.1 to 180.136.63.254180.136.63.2551,022
17180.136.64.0/22180.136.64.1 to 180.136.67.254180.136.67.2551,022
18180.136.68.0/22180.136.68.1 to 180.136.71.254180.136.71.2551,022
19180.136.72.0/22180.136.72.1 to 180.136.75.254180.136.75.2551,022
20180.136.76.0/22180.136.76.1 to 180.136.79.254180.136.79.2551,022
21180.136.80.0/22180.136.80.1 to 180.136.83.254180.136.83.2551,022
22180.136.84.0/22180.136.84.1 to 180.136.87.254180.136.87.2551,022
23180.136.88.0/22180.136.88.1 to 180.136.91.254180.136.91.2551,022
24180.136.92.0/22180.136.92.1 to 180.136.95.254180.136.95.2551,022
25180.136.96.0/22180.136.96.1 to 180.136.99.254180.136.99.2551,022
26180.136.100.0/22180.136.100.1 to 180.136.103.254180.136.103.2551,022
27180.136.104.0/22180.136.104.1 to 180.136.107.254180.136.107.2551,022
28180.136.108.0/22180.136.108.1 to 180.136.111.254180.136.111.2551,022
29180.136.112.0/22180.136.112.1 to 180.136.115.254180.136.115.2551,022
30180.136.116.0/22180.136.116.1 to 180.136.119.254180.136.119.2551,022
31180.136.120.0/22180.136.120.1 to 180.136.123.254180.136.123.2551,022
32180.136.124.0/22180.136.124.1 to 180.136.127.254180.136.127.2551,022
33180.136.128.0/22180.136.128.1 to 180.136.131.254180.136.131.2551,022
34180.136.132.0/22180.136.132.1 to 180.136.135.254180.136.135.2551,022
35180.136.136.0/22180.136.136.1 to 180.136.139.254180.136.139.2551,022
36180.136.140.0/22180.136.140.1 to 180.136.143.254180.136.143.2551,022
37180.136.144.0/22180.136.144.1 to 180.136.147.254180.136.147.2551,022
38180.136.148.0/22180.136.148.1 to 180.136.151.254180.136.151.2551,022
39180.136.152.0/22180.136.152.1 to 180.136.155.254180.136.155.2551,022
40180.136.156.0/22180.136.156.1 to 180.136.159.254180.136.159.2551,022
41180.136.160.0/22180.136.160.1 to 180.136.163.254180.136.163.2551,022
42180.136.164.0/22180.136.164.1 to 180.136.167.254180.136.167.2551,022
43180.136.168.0/22180.136.168.1 to 180.136.171.254180.136.171.2551,022
44180.136.172.0/22180.136.172.1 to 180.136.175.254180.136.175.2551,022
45180.136.176.0/22180.136.176.1 to 180.136.179.254180.136.179.2551,022
46180.136.180.0/22180.136.180.1 to 180.136.183.254180.136.183.2551,022
47180.136.184.0/22180.136.184.1 to 180.136.187.254180.136.187.2551,022
48180.136.188.0/22180.136.188.1 to 180.136.191.254180.136.191.2551,022
49180.136.192.0/22180.136.192.1 to 180.136.195.254180.136.195.2551,022
50180.136.196.0/22180.136.196.1 to 180.136.199.254180.136.199.2551,022
51180.136.200.0/22180.136.200.1 to 180.136.203.254180.136.203.2551,022
52180.136.204.0/22180.136.204.1 to 180.136.207.254180.136.207.2551,022
53180.136.208.0/22180.136.208.1 to 180.136.211.254180.136.211.2551,022
54180.136.212.0/22180.136.212.1 to 180.136.215.254180.136.215.2551,022
55180.136.216.0/22180.136.216.1 to 180.136.219.254180.136.219.2551,022
56180.136.220.0/22180.136.220.1 to 180.136.223.254180.136.223.2551,022
57180.136.224.0/22180.136.224.1 to 180.136.227.254180.136.227.2551,022
58180.136.228.0/22180.136.228.1 to 180.136.231.254180.136.231.2551,022
59180.136.232.0/22180.136.232.1 to 180.136.235.254180.136.235.2551,022
60180.136.236.0/22180.136.236.1 to 180.136.239.254180.136.239.2551,022
61180.136.240.0/22180.136.240.1 to 180.136.243.254180.136.243.2551,022
62180.136.244.0/22180.136.244.1 to 180.136.247.254180.136.247.2551,022
63180.136.248.0/22180.136.248.1 to 180.136.251.254180.136.251.2551,022
64180.136.252.0/22180.136.252.1 to 180.136.255.254180.136.255.2551,022
65180.137.0.0/22180.137.0.1 to 180.137.3.254180.137.3.2551,022
66180.137.4.0/22180.137.4.1 to 180.137.7.254180.137.7.2551,022
67180.137.8.0/22180.137.8.1 to 180.137.11.254180.137.11.2551,022
68180.137.12.0/22180.137.12.1 to 180.137.15.254180.137.15.2551,022
69180.137.16.0/22180.137.16.1 to 180.137.19.254180.137.19.2551,022
70180.137.20.0/22180.137.20.1 to 180.137.23.254180.137.23.2551,022
71180.137.24.0/22180.137.24.1 to 180.137.27.254180.137.27.2551,022
72180.137.28.0/22180.137.28.1 to 180.137.31.254180.137.31.2551,022
73180.137.32.0/22180.137.32.1 to 180.137.35.254180.137.35.2551,022
74180.137.36.0/22180.137.36.1 to 180.137.39.254180.137.39.2551,022
75180.137.40.0/22180.137.40.1 to 180.137.43.254180.137.43.2551,022
76180.137.44.0/22180.137.44.1 to 180.137.47.254180.137.47.2551,022
77180.137.48.0/22180.137.48.1 to 180.137.51.254180.137.51.2551,022
78180.137.52.0/22180.137.52.1 to 180.137.55.254180.137.55.2551,022
79180.137.56.0/22180.137.56.1 to 180.137.59.254180.137.59.2551,022
80180.137.60.0/22180.137.60.1 to 180.137.63.254180.137.63.2551,022
81180.137.64.0/22180.137.64.1 to 180.137.67.254180.137.67.2551,022
82180.137.68.0/22180.137.68.1 to 180.137.71.254180.137.71.2551,022
83180.137.72.0/22180.137.72.1 to 180.137.75.254180.137.75.2551,022
84180.137.76.0/22180.137.76.1 to 180.137.79.254180.137.79.2551,022
85180.137.80.0/22180.137.80.1 to 180.137.83.254180.137.83.2551,022
86180.137.84.0/22180.137.84.1 to 180.137.87.254180.137.87.2551,022
87180.137.88.0/22180.137.88.1 to 180.137.91.254180.137.91.2551,022
88180.137.92.0/22180.137.92.1 to 180.137.95.254180.137.95.2551,022
89180.137.96.0/22180.137.96.1 to 180.137.99.254180.137.99.2551,022
90180.137.100.0/22180.137.100.1 to 180.137.103.254180.137.103.2551,022
91180.137.104.0/22180.137.104.1 to 180.137.107.254180.137.107.2551,022
92180.137.108.0/22180.137.108.1 to 180.137.111.254180.137.111.2551,022
93180.137.112.0/22180.137.112.1 to 180.137.115.254180.137.115.2551,022
94180.137.116.0/22180.137.116.1 to 180.137.119.254180.137.119.2551,022
95180.137.120.0/22180.137.120.1 to 180.137.123.254180.137.123.2551,022
96180.137.124.0/22180.137.124.1 to 180.137.127.254180.137.127.2551,022
97180.137.128.0/22180.137.128.1 to 180.137.131.254180.137.131.2551,022
98180.137.132.0/22180.137.132.1 to 180.137.135.254180.137.135.2551,022
99180.137.136.0/22180.137.136.1 to 180.137.139.254180.137.139.2551,022
100180.137.140.0/22180.137.140.1 to 180.137.143.254180.137.143.2551,022
101180.137.144.0/22180.137.144.1 to 180.137.147.254180.137.147.2551,022
102180.137.148.0/22180.137.148.1 to 180.137.151.254180.137.151.2551,022
103180.137.152.0/22180.137.152.1 to 180.137.155.254180.137.155.2551,022
104180.137.156.0/22180.137.156.1 to 180.137.159.254180.137.159.2551,022
105180.137.160.0/22180.137.160.1 to 180.137.163.254180.137.163.2551,022
106180.137.164.0/22180.137.164.1 to 180.137.167.254180.137.167.2551,022
107180.137.168.0/22180.137.168.1 to 180.137.171.254180.137.171.2551,022
108180.137.172.0/22180.137.172.1 to 180.137.175.254180.137.175.2551,022
109180.137.176.0/22180.137.176.1 to 180.137.179.254180.137.179.2551,022
110180.137.180.0/22180.137.180.1 to 180.137.183.254180.137.183.2551,022
111180.137.184.0/22180.137.184.1 to 180.137.187.254180.137.187.2551,022
112180.137.188.0/22180.137.188.1 to 180.137.191.254180.137.191.2551,022
113180.137.192.0/22180.137.192.1 to 180.137.195.254180.137.195.2551,022
114180.137.196.0/22180.137.196.1 to 180.137.199.254180.137.199.2551,022
115180.137.200.0/22180.137.200.1 to 180.137.203.254180.137.203.2551,022
116180.137.204.0/22180.137.204.1 to 180.137.207.254180.137.207.2551,022
117180.137.208.0/22180.137.208.1 to 180.137.211.254180.137.211.2551,022
118180.137.212.0/22180.137.212.1 to 180.137.215.254180.137.215.2551,022
119180.137.216.0/22180.137.216.1 to 180.137.219.254180.137.219.2551,022
120180.137.220.0/22180.137.220.1 to 180.137.223.254180.137.223.2551,022
121180.137.224.0/22180.137.224.1 to 180.137.227.254180.137.227.2551,022
122180.137.228.0/22180.137.228.1 to 180.137.231.254180.137.231.2551,022
123180.137.232.0/22180.137.232.1 to 180.137.235.254180.137.235.2551,022
124180.137.236.0/22180.137.236.1 to 180.137.239.254180.137.239.2551,022
125180.137.240.0/22180.137.240.1 to 180.137.243.254180.137.243.2551,022
126180.137.244.0/22180.137.244.1 to 180.137.247.254180.137.247.2551,022
127180.137.248.0/22180.137.248.1 to 180.137.251.254180.137.251.2551,022
128180.137.252.0/22180.137.252.1 to 180.137.255.254180.137.255.2551,022
129180.138.0.0/22180.138.0.1 to 180.138.3.254180.138.3.2551,022
130180.138.4.0/22180.138.4.1 to 180.138.7.254180.138.7.2551,022
131180.138.8.0/22180.138.8.1 to 180.138.11.254180.138.11.2551,022
132180.138.12.0/22180.138.12.1 to 180.138.15.254180.138.15.2551,022
133180.138.16.0/22180.138.16.1 to 180.138.19.254180.138.19.2551,022
134180.138.20.0/22180.138.20.1 to 180.138.23.254180.138.23.2551,022
135180.138.24.0/22180.138.24.1 to 180.138.27.254180.138.27.2551,022
136180.138.28.0/22180.138.28.1 to 180.138.31.254180.138.31.2551,022
137180.138.32.0/22180.138.32.1 to 180.138.35.254180.138.35.2551,022
138180.138.36.0/22180.138.36.1 to 180.138.39.254180.138.39.2551,022
139180.138.40.0/22180.138.40.1 to 180.138.43.254180.138.43.2551,022
140180.138.44.0/22180.138.44.1 to 180.138.47.254180.138.47.2551,022
141180.138.48.0/22180.138.48.1 to 180.138.51.254180.138.51.2551,022
142180.138.52.0/22180.138.52.1 to 180.138.55.254180.138.55.2551,022
143180.138.56.0/22180.138.56.1 to 180.138.59.254180.138.59.2551,022
144180.138.60.0/22180.138.60.1 to 180.138.63.254180.138.63.2551,022
145180.138.64.0/22180.138.64.1 to 180.138.67.254180.138.67.2551,022
146180.138.68.0/22180.138.68.1 to 180.138.71.254180.138.71.2551,022
147180.138.72.0/22180.138.72.1 to 180.138.75.254180.138.75.2551,022
148180.138.76.0/22180.138.76.1 to 180.138.79.254180.138.79.2551,022
149180.138.80.0/22180.138.80.1 to 180.138.83.254180.138.83.2551,022
150180.138.84.0/22180.138.84.1 to 180.138.87.254180.138.87.2551,022
151180.138.88.0/22180.138.88.1 to 180.138.91.254180.138.91.2551,022
152180.138.92.0/22180.138.92.1 to 180.138.95.254180.138.95.2551,022
153180.138.96.0/22180.138.96.1 to 180.138.99.254180.138.99.2551,022
154180.138.100.0/22180.138.100.1 to 180.138.103.254180.138.103.2551,022
155180.138.104.0/22180.138.104.1 to 180.138.107.254180.138.107.2551,022
156180.138.108.0/22180.138.108.1 to 180.138.111.254180.138.111.2551,022
157180.138.112.0/22180.138.112.1 to 180.138.115.254180.138.115.2551,022
158180.138.116.0/22180.138.116.1 to 180.138.119.254180.138.119.2551,022
159180.138.120.0/22180.138.120.1 to 180.138.123.254180.138.123.2551,022
160180.138.124.0/22180.138.124.1 to 180.138.127.254180.138.127.2551,022
161180.138.128.0/22180.138.128.1 to 180.138.131.254180.138.131.2551,022
162180.138.132.0/22180.138.132.1 to 180.138.135.254180.138.135.2551,022
163180.138.136.0/22180.138.136.1 to 180.138.139.254180.138.139.2551,022
164180.138.140.0/22180.138.140.1 to 180.138.143.254180.138.143.2551,022
165180.138.144.0/22180.138.144.1 to 180.138.147.254180.138.147.2551,022
166180.138.148.0/22180.138.148.1 to 180.138.151.254180.138.151.2551,022
167180.138.152.0/22180.138.152.1 to 180.138.155.254180.138.155.2551,022
168180.138.156.0/22180.138.156.1 to 180.138.159.254180.138.159.2551,022
169180.138.160.0/22180.138.160.1 to 180.138.163.254180.138.163.2551,022
170180.138.164.0/22180.138.164.1 to 180.138.167.254180.138.167.2551,022
171180.138.168.0/22180.138.168.1 to 180.138.171.254180.138.171.2551,022
172180.138.172.0/22180.138.172.1 to 180.138.175.254180.138.175.2551,022
173180.138.176.0/22180.138.176.1 to 180.138.179.254180.138.179.2551,022
174180.138.180.0/22180.138.180.1 to 180.138.183.254180.138.183.2551,022
175180.138.184.0/22180.138.184.1 to 180.138.187.254180.138.187.2551,022
176180.138.188.0/22180.138.188.1 to 180.138.191.254180.138.191.2551,022
177180.138.192.0/22180.138.192.1 to 180.138.195.254180.138.195.2551,022
178180.138.196.0/22180.138.196.1 to 180.138.199.254180.138.199.2551,022
179180.138.200.0/22180.138.200.1 to 180.138.203.254180.138.203.2551,022
180180.138.204.0/22180.138.204.1 to 180.138.207.254180.138.207.2551,022
181180.138.208.0/22180.138.208.1 to 180.138.211.254180.138.211.2551,022
182180.138.212.0/22180.138.212.1 to 180.138.215.254180.138.215.2551,022
183180.138.216.0/22180.138.216.1 to 180.138.219.254180.138.219.2551,022
184180.138.220.0/22180.138.220.1 to 180.138.223.254180.138.223.2551,022
185180.138.224.0/22180.138.224.1 to 180.138.227.254180.138.227.2551,022
186180.138.228.0/22180.138.228.1 to 180.138.231.254180.138.231.2551,022
187180.138.232.0/22180.138.232.1 to 180.138.235.254180.138.235.2551,022
188180.138.236.0/22180.138.236.1 to 180.138.239.254180.138.239.2551,022
189180.138.240.0/22180.138.240.1 to 180.138.243.254180.138.243.2551,022
190180.138.244.0/22180.138.244.1 to 180.138.247.254180.138.247.2551,022
191180.138.248.0/22180.138.248.1 to 180.138.251.254180.138.251.2551,022
192180.138.252.0/22180.138.252.1 to 180.138.255.254180.138.255.2551,022
193180.139.0.0/22180.139.0.1 to 180.139.3.254180.139.3.2551,022
194180.139.4.0/22180.139.4.1 to 180.139.7.254180.139.7.2551,022
195180.139.8.0/22180.139.8.1 to 180.139.11.254180.139.11.2551,022
196180.139.12.0/22180.139.12.1 to 180.139.15.254180.139.15.2551,022
197180.139.16.0/22180.139.16.1 to 180.139.19.254180.139.19.2551,022
198180.139.20.0/22180.139.20.1 to 180.139.23.254180.139.23.2551,022
199180.139.24.0/22180.139.24.1 to 180.139.27.254180.139.27.2551,022
200180.139.28.0/22180.139.28.1 to 180.139.31.254180.139.31.2551,022
201180.139.32.0/22180.139.32.1 to 180.139.35.254180.139.35.2551,022
202180.139.36.0/22180.139.36.1 to 180.139.39.254180.139.39.2551,022
203180.139.40.0/22180.139.40.1 to 180.139.43.254180.139.43.2551,022
204180.139.44.0/22180.139.44.1 to 180.139.47.254180.139.47.2551,022
205180.139.48.0/22180.139.48.1 to 180.139.51.254180.139.51.2551,022
206180.139.52.0/22180.139.52.1 to 180.139.55.254180.139.55.2551,022
207180.139.56.0/22180.139.56.1 to 180.139.59.254180.139.59.2551,022
208180.139.60.0/22180.139.60.1 to 180.139.63.254180.139.63.2551,022
209180.139.64.0/22180.139.64.1 to 180.139.67.254180.139.67.2551,022
210180.139.68.0/22180.139.68.1 to 180.139.71.254180.139.71.2551,022
211180.139.72.0/22180.139.72.1 to 180.139.75.254180.139.75.2551,022
212180.139.76.0/22180.139.76.1 to 180.139.79.254180.139.79.2551,022
213180.139.80.0/22180.139.80.1 to 180.139.83.254180.139.83.2551,022
214180.139.84.0/22180.139.84.1 to 180.139.87.254180.139.87.2551,022
215180.139.88.0/22180.139.88.1 to 180.139.91.254180.139.91.2551,022
216180.139.92.0/22180.139.92.1 to 180.139.95.254180.139.95.2551,022
217180.139.96.0/22180.139.96.1 to 180.139.99.254180.139.99.2551,022
218180.139.100.0/22180.139.100.1 to 180.139.103.254180.139.103.2551,022
219180.139.104.0/22180.139.104.1 to 180.139.107.254180.139.107.2551,022
220180.139.108.0/22180.139.108.1 to 180.139.111.254180.139.111.2551,022
221180.139.112.0/22180.139.112.1 to 180.139.115.254180.139.115.2551,022
222180.139.116.0/22180.139.116.1 to 180.139.119.254180.139.119.2551,022
223180.139.120.0/22180.139.120.1 to 180.139.123.254180.139.123.2551,022
224180.139.124.0/22180.139.124.1 to 180.139.127.254180.139.127.2551,022
225180.139.128.0/22180.139.128.1 to 180.139.131.254180.139.131.2551,022
226180.139.132.0/22180.139.132.1 to 180.139.135.254180.139.135.2551,022
227180.139.136.0/22180.139.136.1 to 180.139.139.254180.139.139.2551,022
228180.139.140.0/22180.139.140.1 to 180.139.143.254180.139.143.2551,022
229180.139.144.0/22180.139.144.1 to 180.139.147.254180.139.147.2551,022
230180.139.148.0/22180.139.148.1 to 180.139.151.254180.139.151.2551,022
231180.139.152.0/22180.139.152.1 to 180.139.155.254180.139.155.2551,022
232180.139.156.0/22180.139.156.1 to 180.139.159.254180.139.159.2551,022
233180.139.160.0/22180.139.160.1 to 180.139.163.254180.139.163.2551,022
234180.139.164.0/22180.139.164.1 to 180.139.167.254180.139.167.2551,022
235180.139.168.0/22180.139.168.1 to 180.139.171.254180.139.171.2551,022
236180.139.172.0/22180.139.172.1 to 180.139.175.254180.139.175.2551,022
237180.139.176.0/22180.139.176.1 to 180.139.179.254180.139.179.2551,022
238180.139.180.0/22180.139.180.1 to 180.139.183.254180.139.183.2551,022
239180.139.184.0/22180.139.184.1 to 180.139.187.254180.139.187.2551,022
240180.139.188.0/22180.139.188.1 to 180.139.191.254180.139.191.2551,022
241180.139.192.0/22180.139.192.1 to 180.139.195.254180.139.195.2551,022
242180.139.196.0/22180.139.196.1 to 180.139.199.254180.139.199.2551,022
243180.139.200.0/22180.139.200.1 to 180.139.203.254180.139.203.2551,022
244180.139.204.0/22180.139.204.1 to 180.139.207.254180.139.207.2551,022
245180.139.208.0/22180.139.208.1 to 180.139.211.254180.139.211.2551,022
246180.139.212.0/22180.139.212.1 to 180.139.215.254180.139.215.2551,022
247180.139.216.0/22180.139.216.1 to 180.139.219.254180.139.219.2551,022
248180.139.220.0/22180.139.220.1 to 180.139.223.254180.139.223.2551,022
249180.139.224.0/22180.139.224.1 to 180.139.227.254180.139.227.2551,022
250180.139.228.0/22180.139.228.1 to 180.139.231.254180.139.231.2551,022
251180.139.232.0/22180.139.232.1 to 180.139.235.254180.139.235.2551,022
252180.139.236.0/22180.139.236.1 to 180.139.239.254180.139.239.2551,022
253180.139.240.0/22180.139.240.1 to 180.139.243.254180.139.243.2551,022
254180.139.244.0/22180.139.244.1 to 180.139.247.254180.139.247.2551,022
255180.139.248.0/22180.139.248.1 to 180.139.251.254180.139.251.2551,022
256180.139.252.0/22180.139.252.1 to 180.139.255.254180.139.255.2551,022

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.