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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.

Network136.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
136.0.0.0
Broadcast address
139.255.255.255
First usable
136.0.0.1
Last usable
139.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Public public
Old class
B (default /16)
As numbers
Hex 88000000 · Integer 2281701376 to 2348810239
Reverse DNS zones
136.in-addr.arpa
137.in-addr.arpa
138.in-addr.arpa
139.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10001000.00000000.00000000.00000000136.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network10001000.00000000.00000000.00000000136.0.0.0
Broadcast10001011.11111111.11111111.11111111139.255.255.255
Split into smaller subnets/14
/7 (2)/8 (4)/9 (8)/10 (16)/11 (32)/12 (64)/13 (128)/14 (256)/15 (512)/16 (1,024)/17 (2,048)/18 (4,096)

136.0.0.0/6 makes 256 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1136.0.0.0/14136.0.0.1 to 136.3.255.254136.3.255.255262,142
2136.4.0.0/14136.4.0.1 to 136.7.255.254136.7.255.255262,142
3136.8.0.0/14136.8.0.1 to 136.11.255.254136.11.255.255262,142
4136.12.0.0/14136.12.0.1 to 136.15.255.254136.15.255.255262,142
5136.16.0.0/14136.16.0.1 to 136.19.255.254136.19.255.255262,142
6136.20.0.0/14136.20.0.1 to 136.23.255.254136.23.255.255262,142
7136.24.0.0/14136.24.0.1 to 136.27.255.254136.27.255.255262,142
8136.28.0.0/14136.28.0.1 to 136.31.255.254136.31.255.255262,142
9136.32.0.0/14136.32.0.1 to 136.35.255.254136.35.255.255262,142
10136.36.0.0/14136.36.0.1 to 136.39.255.254136.39.255.255262,142
11136.40.0.0/14136.40.0.1 to 136.43.255.254136.43.255.255262,142
12136.44.0.0/14136.44.0.1 to 136.47.255.254136.47.255.255262,142
13136.48.0.0/14136.48.0.1 to 136.51.255.254136.51.255.255262,142
14136.52.0.0/14136.52.0.1 to 136.55.255.254136.55.255.255262,142
15136.56.0.0/14136.56.0.1 to 136.59.255.254136.59.255.255262,142
16136.60.0.0/14136.60.0.1 to 136.63.255.254136.63.255.255262,142
17136.64.0.0/14136.64.0.1 to 136.67.255.254136.67.255.255262,142
18136.68.0.0/14136.68.0.1 to 136.71.255.254136.71.255.255262,142
19136.72.0.0/14136.72.0.1 to 136.75.255.254136.75.255.255262,142
20136.76.0.0/14136.76.0.1 to 136.79.255.254136.79.255.255262,142
21136.80.0.0/14136.80.0.1 to 136.83.255.254136.83.255.255262,142
22136.84.0.0/14136.84.0.1 to 136.87.255.254136.87.255.255262,142
23136.88.0.0/14136.88.0.1 to 136.91.255.254136.91.255.255262,142
24136.92.0.0/14136.92.0.1 to 136.95.255.254136.95.255.255262,142
25136.96.0.0/14136.96.0.1 to 136.99.255.254136.99.255.255262,142
26136.100.0.0/14136.100.0.1 to 136.103.255.254136.103.255.255262,142
27136.104.0.0/14136.104.0.1 to 136.107.255.254136.107.255.255262,142
28136.108.0.0/14136.108.0.1 to 136.111.255.254136.111.255.255262,142
29136.112.0.0/14136.112.0.1 to 136.115.255.254136.115.255.255262,142
30136.116.0.0/14136.116.0.1 to 136.119.255.254136.119.255.255262,142
31136.120.0.0/14136.120.0.1 to 136.123.255.254136.123.255.255262,142
32136.124.0.0/14136.124.0.1 to 136.127.255.254136.127.255.255262,142
33136.128.0.0/14136.128.0.1 to 136.131.255.254136.131.255.255262,142
34136.132.0.0/14136.132.0.1 to 136.135.255.254136.135.255.255262,142
35136.136.0.0/14136.136.0.1 to 136.139.255.254136.139.255.255262,142
36136.140.0.0/14136.140.0.1 to 136.143.255.254136.143.255.255262,142
37136.144.0.0/14136.144.0.1 to 136.147.255.254136.147.255.255262,142
38136.148.0.0/14136.148.0.1 to 136.151.255.254136.151.255.255262,142
39136.152.0.0/14136.152.0.1 to 136.155.255.254136.155.255.255262,142
40136.156.0.0/14136.156.0.1 to 136.159.255.254136.159.255.255262,142
41136.160.0.0/14136.160.0.1 to 136.163.255.254136.163.255.255262,142
42136.164.0.0/14136.164.0.1 to 136.167.255.254136.167.255.255262,142
43136.168.0.0/14136.168.0.1 to 136.171.255.254136.171.255.255262,142
44136.172.0.0/14136.172.0.1 to 136.175.255.254136.175.255.255262,142
45136.176.0.0/14136.176.0.1 to 136.179.255.254136.179.255.255262,142
46136.180.0.0/14136.180.0.1 to 136.183.255.254136.183.255.255262,142
47136.184.0.0/14136.184.0.1 to 136.187.255.254136.187.255.255262,142
48136.188.0.0/14136.188.0.1 to 136.191.255.254136.191.255.255262,142
49136.192.0.0/14136.192.0.1 to 136.195.255.254136.195.255.255262,142
50136.196.0.0/14136.196.0.1 to 136.199.255.254136.199.255.255262,142
51136.200.0.0/14136.200.0.1 to 136.203.255.254136.203.255.255262,142
52136.204.0.0/14136.204.0.1 to 136.207.255.254136.207.255.255262,142
53136.208.0.0/14136.208.0.1 to 136.211.255.254136.211.255.255262,142
54136.212.0.0/14136.212.0.1 to 136.215.255.254136.215.255.255262,142
55136.216.0.0/14136.216.0.1 to 136.219.255.254136.219.255.255262,142
56136.220.0.0/14136.220.0.1 to 136.223.255.254136.223.255.255262,142
57136.224.0.0/14136.224.0.1 to 136.227.255.254136.227.255.255262,142
58136.228.0.0/14136.228.0.1 to 136.231.255.254136.231.255.255262,142
59136.232.0.0/14136.232.0.1 to 136.235.255.254136.235.255.255262,142
60136.236.0.0/14136.236.0.1 to 136.239.255.254136.239.255.255262,142
61136.240.0.0/14136.240.0.1 to 136.243.255.254136.243.255.255262,142
62136.244.0.0/14136.244.0.1 to 136.247.255.254136.247.255.255262,142
63136.248.0.0/14136.248.0.1 to 136.251.255.254136.251.255.255262,142
64136.252.0.0/14136.252.0.1 to 136.255.255.254136.255.255.255262,142
65137.0.0.0/14137.0.0.1 to 137.3.255.254137.3.255.255262,142
66137.4.0.0/14137.4.0.1 to 137.7.255.254137.7.255.255262,142
67137.8.0.0/14137.8.0.1 to 137.11.255.254137.11.255.255262,142
68137.12.0.0/14137.12.0.1 to 137.15.255.254137.15.255.255262,142
69137.16.0.0/14137.16.0.1 to 137.19.255.254137.19.255.255262,142
70137.20.0.0/14137.20.0.1 to 137.23.255.254137.23.255.255262,142
71137.24.0.0/14137.24.0.1 to 137.27.255.254137.27.255.255262,142
72137.28.0.0/14137.28.0.1 to 137.31.255.254137.31.255.255262,142
73137.32.0.0/14137.32.0.1 to 137.35.255.254137.35.255.255262,142
74137.36.0.0/14137.36.0.1 to 137.39.255.254137.39.255.255262,142
75137.40.0.0/14137.40.0.1 to 137.43.255.254137.43.255.255262,142
76137.44.0.0/14137.44.0.1 to 137.47.255.254137.47.255.255262,142
77137.48.0.0/14137.48.0.1 to 137.51.255.254137.51.255.255262,142
78137.52.0.0/14137.52.0.1 to 137.55.255.254137.55.255.255262,142
79137.56.0.0/14137.56.0.1 to 137.59.255.254137.59.255.255262,142
80137.60.0.0/14137.60.0.1 to 137.63.255.254137.63.255.255262,142
81137.64.0.0/14137.64.0.1 to 137.67.255.254137.67.255.255262,142
82137.68.0.0/14137.68.0.1 to 137.71.255.254137.71.255.255262,142
83137.72.0.0/14137.72.0.1 to 137.75.255.254137.75.255.255262,142
84137.76.0.0/14137.76.0.1 to 137.79.255.254137.79.255.255262,142
85137.80.0.0/14137.80.0.1 to 137.83.255.254137.83.255.255262,142
86137.84.0.0/14137.84.0.1 to 137.87.255.254137.87.255.255262,142
87137.88.0.0/14137.88.0.1 to 137.91.255.254137.91.255.255262,142
88137.92.0.0/14137.92.0.1 to 137.95.255.254137.95.255.255262,142
89137.96.0.0/14137.96.0.1 to 137.99.255.254137.99.255.255262,142
90137.100.0.0/14137.100.0.1 to 137.103.255.254137.103.255.255262,142
91137.104.0.0/14137.104.0.1 to 137.107.255.254137.107.255.255262,142
92137.108.0.0/14137.108.0.1 to 137.111.255.254137.111.255.255262,142
93137.112.0.0/14137.112.0.1 to 137.115.255.254137.115.255.255262,142
94137.116.0.0/14137.116.0.1 to 137.119.255.254137.119.255.255262,142
95137.120.0.0/14137.120.0.1 to 137.123.255.254137.123.255.255262,142
96137.124.0.0/14137.124.0.1 to 137.127.255.254137.127.255.255262,142
97137.128.0.0/14137.128.0.1 to 137.131.255.254137.131.255.255262,142
98137.132.0.0/14137.132.0.1 to 137.135.255.254137.135.255.255262,142
99137.136.0.0/14137.136.0.1 to 137.139.255.254137.139.255.255262,142
100137.140.0.0/14137.140.0.1 to 137.143.255.254137.143.255.255262,142
101137.144.0.0/14137.144.0.1 to 137.147.255.254137.147.255.255262,142
102137.148.0.0/14137.148.0.1 to 137.151.255.254137.151.255.255262,142
103137.152.0.0/14137.152.0.1 to 137.155.255.254137.155.255.255262,142
104137.156.0.0/14137.156.0.1 to 137.159.255.254137.159.255.255262,142
105137.160.0.0/14137.160.0.1 to 137.163.255.254137.163.255.255262,142
106137.164.0.0/14137.164.0.1 to 137.167.255.254137.167.255.255262,142
107137.168.0.0/14137.168.0.1 to 137.171.255.254137.171.255.255262,142
108137.172.0.0/14137.172.0.1 to 137.175.255.254137.175.255.255262,142
109137.176.0.0/14137.176.0.1 to 137.179.255.254137.179.255.255262,142
110137.180.0.0/14137.180.0.1 to 137.183.255.254137.183.255.255262,142
111137.184.0.0/14137.184.0.1 to 137.187.255.254137.187.255.255262,142
112137.188.0.0/14137.188.0.1 to 137.191.255.254137.191.255.255262,142
113137.192.0.0/14137.192.0.1 to 137.195.255.254137.195.255.255262,142
114137.196.0.0/14137.196.0.1 to 137.199.255.254137.199.255.255262,142
115137.200.0.0/14137.200.0.1 to 137.203.255.254137.203.255.255262,142
116137.204.0.0/14137.204.0.1 to 137.207.255.254137.207.255.255262,142
117137.208.0.0/14137.208.0.1 to 137.211.255.254137.211.255.255262,142
118137.212.0.0/14137.212.0.1 to 137.215.255.254137.215.255.255262,142
119137.216.0.0/14137.216.0.1 to 137.219.255.254137.219.255.255262,142
120137.220.0.0/14137.220.0.1 to 137.223.255.254137.223.255.255262,142
121137.224.0.0/14137.224.0.1 to 137.227.255.254137.227.255.255262,142
122137.228.0.0/14137.228.0.1 to 137.231.255.254137.231.255.255262,142
123137.232.0.0/14137.232.0.1 to 137.235.255.254137.235.255.255262,142
124137.236.0.0/14137.236.0.1 to 137.239.255.254137.239.255.255262,142
125137.240.0.0/14137.240.0.1 to 137.243.255.254137.243.255.255262,142
126137.244.0.0/14137.244.0.1 to 137.247.255.254137.247.255.255262,142
127137.248.0.0/14137.248.0.1 to 137.251.255.254137.251.255.255262,142
128137.252.0.0/14137.252.0.1 to 137.255.255.254137.255.255.255262,142
129138.0.0.0/14138.0.0.1 to 138.3.255.254138.3.255.255262,142
130138.4.0.0/14138.4.0.1 to 138.7.255.254138.7.255.255262,142
131138.8.0.0/14138.8.0.1 to 138.11.255.254138.11.255.255262,142
132138.12.0.0/14138.12.0.1 to 138.15.255.254138.15.255.255262,142
133138.16.0.0/14138.16.0.1 to 138.19.255.254138.19.255.255262,142
134138.20.0.0/14138.20.0.1 to 138.23.255.254138.23.255.255262,142
135138.24.0.0/14138.24.0.1 to 138.27.255.254138.27.255.255262,142
136138.28.0.0/14138.28.0.1 to 138.31.255.254138.31.255.255262,142
137138.32.0.0/14138.32.0.1 to 138.35.255.254138.35.255.255262,142
138138.36.0.0/14138.36.0.1 to 138.39.255.254138.39.255.255262,142
139138.40.0.0/14138.40.0.1 to 138.43.255.254138.43.255.255262,142
140138.44.0.0/14138.44.0.1 to 138.47.255.254138.47.255.255262,142
141138.48.0.0/14138.48.0.1 to 138.51.255.254138.51.255.255262,142
142138.52.0.0/14138.52.0.1 to 138.55.255.254138.55.255.255262,142
143138.56.0.0/14138.56.0.1 to 138.59.255.254138.59.255.255262,142
144138.60.0.0/14138.60.0.1 to 138.63.255.254138.63.255.255262,142
145138.64.0.0/14138.64.0.1 to 138.67.255.254138.67.255.255262,142
146138.68.0.0/14138.68.0.1 to 138.71.255.254138.71.255.255262,142
147138.72.0.0/14138.72.0.1 to 138.75.255.254138.75.255.255262,142
148138.76.0.0/14138.76.0.1 to 138.79.255.254138.79.255.255262,142
149138.80.0.0/14138.80.0.1 to 138.83.255.254138.83.255.255262,142
150138.84.0.0/14138.84.0.1 to 138.87.255.254138.87.255.255262,142
151138.88.0.0/14138.88.0.1 to 138.91.255.254138.91.255.255262,142
152138.92.0.0/14138.92.0.1 to 138.95.255.254138.95.255.255262,142
153138.96.0.0/14138.96.0.1 to 138.99.255.254138.99.255.255262,142
154138.100.0.0/14138.100.0.1 to 138.103.255.254138.103.255.255262,142
155138.104.0.0/14138.104.0.1 to 138.107.255.254138.107.255.255262,142
156138.108.0.0/14138.108.0.1 to 138.111.255.254138.111.255.255262,142
157138.112.0.0/14138.112.0.1 to 138.115.255.254138.115.255.255262,142
158138.116.0.0/14138.116.0.1 to 138.119.255.254138.119.255.255262,142
159138.120.0.0/14138.120.0.1 to 138.123.255.254138.123.255.255262,142
160138.124.0.0/14138.124.0.1 to 138.127.255.254138.127.255.255262,142
161138.128.0.0/14138.128.0.1 to 138.131.255.254138.131.255.255262,142
162138.132.0.0/14138.132.0.1 to 138.135.255.254138.135.255.255262,142
163138.136.0.0/14138.136.0.1 to 138.139.255.254138.139.255.255262,142
164138.140.0.0/14138.140.0.1 to 138.143.255.254138.143.255.255262,142
165138.144.0.0/14138.144.0.1 to 138.147.255.254138.147.255.255262,142
166138.148.0.0/14138.148.0.1 to 138.151.255.254138.151.255.255262,142
167138.152.0.0/14138.152.0.1 to 138.155.255.254138.155.255.255262,142
168138.156.0.0/14138.156.0.1 to 138.159.255.254138.159.255.255262,142
169138.160.0.0/14138.160.0.1 to 138.163.255.254138.163.255.255262,142
170138.164.0.0/14138.164.0.1 to 138.167.255.254138.167.255.255262,142
171138.168.0.0/14138.168.0.1 to 138.171.255.254138.171.255.255262,142
172138.172.0.0/14138.172.0.1 to 138.175.255.254138.175.255.255262,142
173138.176.0.0/14138.176.0.1 to 138.179.255.254138.179.255.255262,142
174138.180.0.0/14138.180.0.1 to 138.183.255.254138.183.255.255262,142
175138.184.0.0/14138.184.0.1 to 138.187.255.254138.187.255.255262,142
176138.188.0.0/14138.188.0.1 to 138.191.255.254138.191.255.255262,142
177138.192.0.0/14138.192.0.1 to 138.195.255.254138.195.255.255262,142
178138.196.0.0/14138.196.0.1 to 138.199.255.254138.199.255.255262,142
179138.200.0.0/14138.200.0.1 to 138.203.255.254138.203.255.255262,142
180138.204.0.0/14138.204.0.1 to 138.207.255.254138.207.255.255262,142
181138.208.0.0/14138.208.0.1 to 138.211.255.254138.211.255.255262,142
182138.212.0.0/14138.212.0.1 to 138.215.255.254138.215.255.255262,142
183138.216.0.0/14138.216.0.1 to 138.219.255.254138.219.255.255262,142
184138.220.0.0/14138.220.0.1 to 138.223.255.254138.223.255.255262,142
185138.224.0.0/14138.224.0.1 to 138.227.255.254138.227.255.255262,142
186138.228.0.0/14138.228.0.1 to 138.231.255.254138.231.255.255262,142
187138.232.0.0/14138.232.0.1 to 138.235.255.254138.235.255.255262,142
188138.236.0.0/14138.236.0.1 to 138.239.255.254138.239.255.255262,142
189138.240.0.0/14138.240.0.1 to 138.243.255.254138.243.255.255262,142
190138.244.0.0/14138.244.0.1 to 138.247.255.254138.247.255.255262,142
191138.248.0.0/14138.248.0.1 to 138.251.255.254138.251.255.255262,142
192138.252.0.0/14138.252.0.1 to 138.255.255.254138.255.255.255262,142
193139.0.0.0/14139.0.0.1 to 139.3.255.254139.3.255.255262,142
194139.4.0.0/14139.4.0.1 to 139.7.255.254139.7.255.255262,142
195139.8.0.0/14139.8.0.1 to 139.11.255.254139.11.255.255262,142
196139.12.0.0/14139.12.0.1 to 139.15.255.254139.15.255.255262,142
197139.16.0.0/14139.16.0.1 to 139.19.255.254139.19.255.255262,142
198139.20.0.0/14139.20.0.1 to 139.23.255.254139.23.255.255262,142
199139.24.0.0/14139.24.0.1 to 139.27.255.254139.27.255.255262,142
200139.28.0.0/14139.28.0.1 to 139.31.255.254139.31.255.255262,142
201139.32.0.0/14139.32.0.1 to 139.35.255.254139.35.255.255262,142
202139.36.0.0/14139.36.0.1 to 139.39.255.254139.39.255.255262,142
203139.40.0.0/14139.40.0.1 to 139.43.255.254139.43.255.255262,142
204139.44.0.0/14139.44.0.1 to 139.47.255.254139.47.255.255262,142
205139.48.0.0/14139.48.0.1 to 139.51.255.254139.51.255.255262,142
206139.52.0.0/14139.52.0.1 to 139.55.255.254139.55.255.255262,142
207139.56.0.0/14139.56.0.1 to 139.59.255.254139.59.255.255262,142
208139.60.0.0/14139.60.0.1 to 139.63.255.254139.63.255.255262,142
209139.64.0.0/14139.64.0.1 to 139.67.255.254139.67.255.255262,142
210139.68.0.0/14139.68.0.1 to 139.71.255.254139.71.255.255262,142
211139.72.0.0/14139.72.0.1 to 139.75.255.254139.75.255.255262,142
212139.76.0.0/14139.76.0.1 to 139.79.255.254139.79.255.255262,142
213139.80.0.0/14139.80.0.1 to 139.83.255.254139.83.255.255262,142
214139.84.0.0/14139.84.0.1 to 139.87.255.254139.87.255.255262,142
215139.88.0.0/14139.88.0.1 to 139.91.255.254139.91.255.255262,142
216139.92.0.0/14139.92.0.1 to 139.95.255.254139.95.255.255262,142
217139.96.0.0/14139.96.0.1 to 139.99.255.254139.99.255.255262,142
218139.100.0.0/14139.100.0.1 to 139.103.255.254139.103.255.255262,142
219139.104.0.0/14139.104.0.1 to 139.107.255.254139.107.255.255262,142
220139.108.0.0/14139.108.0.1 to 139.111.255.254139.111.255.255262,142
221139.112.0.0/14139.112.0.1 to 139.115.255.254139.115.255.255262,142
222139.116.0.0/14139.116.0.1 to 139.119.255.254139.119.255.255262,142
223139.120.0.0/14139.120.0.1 to 139.123.255.254139.123.255.255262,142
224139.124.0.0/14139.124.0.1 to 139.127.255.254139.127.255.255262,142
225139.128.0.0/14139.128.0.1 to 139.131.255.254139.131.255.255262,142
226139.132.0.0/14139.132.0.1 to 139.135.255.254139.135.255.255262,142
227139.136.0.0/14139.136.0.1 to 139.139.255.254139.139.255.255262,142
228139.140.0.0/14139.140.0.1 to 139.143.255.254139.143.255.255262,142
229139.144.0.0/14139.144.0.1 to 139.147.255.254139.147.255.255262,142
230139.148.0.0/14139.148.0.1 to 139.151.255.254139.151.255.255262,142
231139.152.0.0/14139.152.0.1 to 139.155.255.254139.155.255.255262,142
232139.156.0.0/14139.156.0.1 to 139.159.255.254139.159.255.255262,142
233139.160.0.0/14139.160.0.1 to 139.163.255.254139.163.255.255262,142
234139.164.0.0/14139.164.0.1 to 139.167.255.254139.167.255.255262,142
235139.168.0.0/14139.168.0.1 to 139.171.255.254139.171.255.255262,142
236139.172.0.0/14139.172.0.1 to 139.175.255.254139.175.255.255262,142
237139.176.0.0/14139.176.0.1 to 139.179.255.254139.179.255.255262,142
238139.180.0.0/14139.180.0.1 to 139.183.255.254139.183.255.255262,142
239139.184.0.0/14139.184.0.1 to 139.187.255.254139.187.255.255262,142
240139.188.0.0/14139.188.0.1 to 139.191.255.254139.191.255.255262,142
241139.192.0.0/14139.192.0.1 to 139.195.255.254139.195.255.255262,142
242139.196.0.0/14139.196.0.1 to 139.199.255.254139.199.255.255262,142
243139.200.0.0/14139.200.0.1 to 139.203.255.254139.203.255.255262,142
244139.204.0.0/14139.204.0.1 to 139.207.255.254139.207.255.255262,142
245139.208.0.0/14139.208.0.1 to 139.211.255.254139.211.255.255262,142
246139.212.0.0/14139.212.0.1 to 139.215.255.254139.215.255.255262,142
247139.216.0.0/14139.216.0.1 to 139.219.255.254139.219.255.255262,142
248139.220.0.0/14139.220.0.1 to 139.223.255.254139.223.255.255262,142
249139.224.0.0/14139.224.0.1 to 139.227.255.254139.227.255.255262,142
250139.228.0.0/14139.228.0.1 to 139.231.255.254139.231.255.255262,142
251139.232.0.0/14139.232.0.1 to 139.235.255.254139.235.255.255262,142
252139.236.0.0/14139.236.0.1 to 139.239.255.254139.239.255.255262,142
253139.240.0.0/14139.240.0.1 to 139.243.255.254139.243.255.255262,142
254139.244.0.0/14139.244.0.1 to 139.247.255.254139.247.255.255262,142
255139.248.0.0/14139.248.0.1 to 139.251.255.254139.251.255.255262,142
256139.252.0.0/14139.252.0.1 to 139.255.255.254139.255.255.255262,142

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.