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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.

Network119.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
119.0.0.0
Broadcast address
119.127.255.255
First usable
119.0.0.1
Last usable
119.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 77000000 · Integer 1996488704 to 2004877311
Reverse DNS zones
0.119.in-addr.arpa
1.119.in-addr.arpa
2.119.in-addr.arpa
3.119.in-addr.arpa
4.119.in-addr.arpa
5.119.in-addr.arpa
6.119.in-addr.arpa
7.119.in-addr.arpa
8.119.in-addr.arpa
9.119.in-addr.arpa
10.119.in-addr.arpa
11.119.in-addr.arpa
12.119.in-addr.arpa
13.119.in-addr.arpa
14.119.in-addr.arpa
15.119.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110111.00000000.00000000.00000000119.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01110111.00000000.00000000.00000000119.0.0.0
Broadcast01110111.01111111.11111111.11111111119.127.255.255
Split into smaller subnets/21
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

119.0.0.0/9 makes 4,096 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1119.0.0.0/21119.0.0.1 to 119.0.7.254119.0.7.2552,046
2119.0.8.0/21119.0.8.1 to 119.0.15.254119.0.15.2552,046
3119.0.16.0/21119.0.16.1 to 119.0.23.254119.0.23.2552,046
4119.0.24.0/21119.0.24.1 to 119.0.31.254119.0.31.2552,046
5119.0.32.0/21119.0.32.1 to 119.0.39.254119.0.39.2552,046
6119.0.40.0/21119.0.40.1 to 119.0.47.254119.0.47.2552,046
7119.0.48.0/21119.0.48.1 to 119.0.55.254119.0.55.2552,046
8119.0.56.0/21119.0.56.1 to 119.0.63.254119.0.63.2552,046
9119.0.64.0/21119.0.64.1 to 119.0.71.254119.0.71.2552,046
10119.0.72.0/21119.0.72.1 to 119.0.79.254119.0.79.2552,046
11119.0.80.0/21119.0.80.1 to 119.0.87.254119.0.87.2552,046
12119.0.88.0/21119.0.88.1 to 119.0.95.254119.0.95.2552,046
13119.0.96.0/21119.0.96.1 to 119.0.103.254119.0.103.2552,046
14119.0.104.0/21119.0.104.1 to 119.0.111.254119.0.111.2552,046
15119.0.112.0/21119.0.112.1 to 119.0.119.254119.0.119.2552,046
16119.0.120.0/21119.0.120.1 to 119.0.127.254119.0.127.2552,046
17119.0.128.0/21119.0.128.1 to 119.0.135.254119.0.135.2552,046
18119.0.136.0/21119.0.136.1 to 119.0.143.254119.0.143.2552,046
19119.0.144.0/21119.0.144.1 to 119.0.151.254119.0.151.2552,046
20119.0.152.0/21119.0.152.1 to 119.0.159.254119.0.159.2552,046
21119.0.160.0/21119.0.160.1 to 119.0.167.254119.0.167.2552,046
22119.0.168.0/21119.0.168.1 to 119.0.175.254119.0.175.2552,046
23119.0.176.0/21119.0.176.1 to 119.0.183.254119.0.183.2552,046
24119.0.184.0/21119.0.184.1 to 119.0.191.254119.0.191.2552,046
25119.0.192.0/21119.0.192.1 to 119.0.199.254119.0.199.2552,046
26119.0.200.0/21119.0.200.1 to 119.0.207.254119.0.207.2552,046
27119.0.208.0/21119.0.208.1 to 119.0.215.254119.0.215.2552,046
28119.0.216.0/21119.0.216.1 to 119.0.223.254119.0.223.2552,046
29119.0.224.0/21119.0.224.1 to 119.0.231.254119.0.231.2552,046
30119.0.232.0/21119.0.232.1 to 119.0.239.254119.0.239.2552,046
31119.0.240.0/21119.0.240.1 to 119.0.247.254119.0.247.2552,046
32119.0.248.0/21119.0.248.1 to 119.0.255.254119.0.255.2552,046
33119.1.0.0/21119.1.0.1 to 119.1.7.254119.1.7.2552,046
34119.1.8.0/21119.1.8.1 to 119.1.15.254119.1.15.2552,046
35119.1.16.0/21119.1.16.1 to 119.1.23.254119.1.23.2552,046
36119.1.24.0/21119.1.24.1 to 119.1.31.254119.1.31.2552,046
37119.1.32.0/21119.1.32.1 to 119.1.39.254119.1.39.2552,046
38119.1.40.0/21119.1.40.1 to 119.1.47.254119.1.47.2552,046
39119.1.48.0/21119.1.48.1 to 119.1.55.254119.1.55.2552,046
40119.1.56.0/21119.1.56.1 to 119.1.63.254119.1.63.2552,046
41119.1.64.0/21119.1.64.1 to 119.1.71.254119.1.71.2552,046
42119.1.72.0/21119.1.72.1 to 119.1.79.254119.1.79.2552,046
43119.1.80.0/21119.1.80.1 to 119.1.87.254119.1.87.2552,046
44119.1.88.0/21119.1.88.1 to 119.1.95.254119.1.95.2552,046
45119.1.96.0/21119.1.96.1 to 119.1.103.254119.1.103.2552,046
46119.1.104.0/21119.1.104.1 to 119.1.111.254119.1.111.2552,046
47119.1.112.0/21119.1.112.1 to 119.1.119.254119.1.119.2552,046
48119.1.120.0/21119.1.120.1 to 119.1.127.254119.1.127.2552,046
49119.1.128.0/21119.1.128.1 to 119.1.135.254119.1.135.2552,046
50119.1.136.0/21119.1.136.1 to 119.1.143.254119.1.143.2552,046
51119.1.144.0/21119.1.144.1 to 119.1.151.254119.1.151.2552,046
52119.1.152.0/21119.1.152.1 to 119.1.159.254119.1.159.2552,046
53119.1.160.0/21119.1.160.1 to 119.1.167.254119.1.167.2552,046
54119.1.168.0/21119.1.168.1 to 119.1.175.254119.1.175.2552,046
55119.1.176.0/21119.1.176.1 to 119.1.183.254119.1.183.2552,046
56119.1.184.0/21119.1.184.1 to 119.1.191.254119.1.191.2552,046
57119.1.192.0/21119.1.192.1 to 119.1.199.254119.1.199.2552,046
58119.1.200.0/21119.1.200.1 to 119.1.207.254119.1.207.2552,046
59119.1.208.0/21119.1.208.1 to 119.1.215.254119.1.215.2552,046
60119.1.216.0/21119.1.216.1 to 119.1.223.254119.1.223.2552,046
61119.1.224.0/21119.1.224.1 to 119.1.231.254119.1.231.2552,046
62119.1.232.0/21119.1.232.1 to 119.1.239.254119.1.239.2552,046
63119.1.240.0/21119.1.240.1 to 119.1.247.254119.1.247.2552,046
64119.1.248.0/21119.1.248.1 to 119.1.255.254119.1.255.2552,046
65119.2.0.0/21119.2.0.1 to 119.2.7.254119.2.7.2552,046
66119.2.8.0/21119.2.8.1 to 119.2.15.254119.2.15.2552,046
67119.2.16.0/21119.2.16.1 to 119.2.23.254119.2.23.2552,046
68119.2.24.0/21119.2.24.1 to 119.2.31.254119.2.31.2552,046
69119.2.32.0/21119.2.32.1 to 119.2.39.254119.2.39.2552,046
70119.2.40.0/21119.2.40.1 to 119.2.47.254119.2.47.2552,046
71119.2.48.0/21119.2.48.1 to 119.2.55.254119.2.55.2552,046
72119.2.56.0/21119.2.56.1 to 119.2.63.254119.2.63.2552,046
73119.2.64.0/21119.2.64.1 to 119.2.71.254119.2.71.2552,046
74119.2.72.0/21119.2.72.1 to 119.2.79.254119.2.79.2552,046
75119.2.80.0/21119.2.80.1 to 119.2.87.254119.2.87.2552,046
76119.2.88.0/21119.2.88.1 to 119.2.95.254119.2.95.2552,046
77119.2.96.0/21119.2.96.1 to 119.2.103.254119.2.103.2552,046
78119.2.104.0/21119.2.104.1 to 119.2.111.254119.2.111.2552,046
79119.2.112.0/21119.2.112.1 to 119.2.119.254119.2.119.2552,046
80119.2.120.0/21119.2.120.1 to 119.2.127.254119.2.127.2552,046
81119.2.128.0/21119.2.128.1 to 119.2.135.254119.2.135.2552,046
82119.2.136.0/21119.2.136.1 to 119.2.143.254119.2.143.2552,046
83119.2.144.0/21119.2.144.1 to 119.2.151.254119.2.151.2552,046
84119.2.152.0/21119.2.152.1 to 119.2.159.254119.2.159.2552,046
85119.2.160.0/21119.2.160.1 to 119.2.167.254119.2.167.2552,046
86119.2.168.0/21119.2.168.1 to 119.2.175.254119.2.175.2552,046
87119.2.176.0/21119.2.176.1 to 119.2.183.254119.2.183.2552,046
88119.2.184.0/21119.2.184.1 to 119.2.191.254119.2.191.2552,046
89119.2.192.0/21119.2.192.1 to 119.2.199.254119.2.199.2552,046
90119.2.200.0/21119.2.200.1 to 119.2.207.254119.2.207.2552,046
91119.2.208.0/21119.2.208.1 to 119.2.215.254119.2.215.2552,046
92119.2.216.0/21119.2.216.1 to 119.2.223.254119.2.223.2552,046
93119.2.224.0/21119.2.224.1 to 119.2.231.254119.2.231.2552,046
94119.2.232.0/21119.2.232.1 to 119.2.239.254119.2.239.2552,046
95119.2.240.0/21119.2.240.1 to 119.2.247.254119.2.247.2552,046
96119.2.248.0/21119.2.248.1 to 119.2.255.254119.2.255.2552,046
97119.3.0.0/21119.3.0.1 to 119.3.7.254119.3.7.2552,046
98119.3.8.0/21119.3.8.1 to 119.3.15.254119.3.15.2552,046
99119.3.16.0/21119.3.16.1 to 119.3.23.254119.3.23.2552,046
100119.3.24.0/21119.3.24.1 to 119.3.31.254119.3.31.2552,046
101119.3.32.0/21119.3.32.1 to 119.3.39.254119.3.39.2552,046
102119.3.40.0/21119.3.40.1 to 119.3.47.254119.3.47.2552,046
103119.3.48.0/21119.3.48.1 to 119.3.55.254119.3.55.2552,046
104119.3.56.0/21119.3.56.1 to 119.3.63.254119.3.63.2552,046
105119.3.64.0/21119.3.64.1 to 119.3.71.254119.3.71.2552,046
106119.3.72.0/21119.3.72.1 to 119.3.79.254119.3.79.2552,046
107119.3.80.0/21119.3.80.1 to 119.3.87.254119.3.87.2552,046
108119.3.88.0/21119.3.88.1 to 119.3.95.254119.3.95.2552,046
109119.3.96.0/21119.3.96.1 to 119.3.103.254119.3.103.2552,046
110119.3.104.0/21119.3.104.1 to 119.3.111.254119.3.111.2552,046
111119.3.112.0/21119.3.112.1 to 119.3.119.254119.3.119.2552,046
112119.3.120.0/21119.3.120.1 to 119.3.127.254119.3.127.2552,046
113119.3.128.0/21119.3.128.1 to 119.3.135.254119.3.135.2552,046
114119.3.136.0/21119.3.136.1 to 119.3.143.254119.3.143.2552,046
115119.3.144.0/21119.3.144.1 to 119.3.151.254119.3.151.2552,046
116119.3.152.0/21119.3.152.1 to 119.3.159.254119.3.159.2552,046
117119.3.160.0/21119.3.160.1 to 119.3.167.254119.3.167.2552,046
118119.3.168.0/21119.3.168.1 to 119.3.175.254119.3.175.2552,046
119119.3.176.0/21119.3.176.1 to 119.3.183.254119.3.183.2552,046
120119.3.184.0/21119.3.184.1 to 119.3.191.254119.3.191.2552,046
121119.3.192.0/21119.3.192.1 to 119.3.199.254119.3.199.2552,046
122119.3.200.0/21119.3.200.1 to 119.3.207.254119.3.207.2552,046
123119.3.208.0/21119.3.208.1 to 119.3.215.254119.3.215.2552,046
124119.3.216.0/21119.3.216.1 to 119.3.223.254119.3.223.2552,046
125119.3.224.0/21119.3.224.1 to 119.3.231.254119.3.231.2552,046
126119.3.232.0/21119.3.232.1 to 119.3.239.254119.3.239.2552,046
127119.3.240.0/21119.3.240.1 to 119.3.247.254119.3.247.2552,046
128119.3.248.0/21119.3.248.1 to 119.3.255.254119.3.255.2552,046
129119.4.0.0/21119.4.0.1 to 119.4.7.254119.4.7.2552,046
130119.4.8.0/21119.4.8.1 to 119.4.15.254119.4.15.2552,046
131119.4.16.0/21119.4.16.1 to 119.4.23.254119.4.23.2552,046
132119.4.24.0/21119.4.24.1 to 119.4.31.254119.4.31.2552,046
133119.4.32.0/21119.4.32.1 to 119.4.39.254119.4.39.2552,046
134119.4.40.0/21119.4.40.1 to 119.4.47.254119.4.47.2552,046
135119.4.48.0/21119.4.48.1 to 119.4.55.254119.4.55.2552,046
136119.4.56.0/21119.4.56.1 to 119.4.63.254119.4.63.2552,046
137119.4.64.0/21119.4.64.1 to 119.4.71.254119.4.71.2552,046
138119.4.72.0/21119.4.72.1 to 119.4.79.254119.4.79.2552,046
139119.4.80.0/21119.4.80.1 to 119.4.87.254119.4.87.2552,046
140119.4.88.0/21119.4.88.1 to 119.4.95.254119.4.95.2552,046
141119.4.96.0/21119.4.96.1 to 119.4.103.254119.4.103.2552,046
142119.4.104.0/21119.4.104.1 to 119.4.111.254119.4.111.2552,046
143119.4.112.0/21119.4.112.1 to 119.4.119.254119.4.119.2552,046
144119.4.120.0/21119.4.120.1 to 119.4.127.254119.4.127.2552,046
145119.4.128.0/21119.4.128.1 to 119.4.135.254119.4.135.2552,046
146119.4.136.0/21119.4.136.1 to 119.4.143.254119.4.143.2552,046
147119.4.144.0/21119.4.144.1 to 119.4.151.254119.4.151.2552,046
148119.4.152.0/21119.4.152.1 to 119.4.159.254119.4.159.2552,046
149119.4.160.0/21119.4.160.1 to 119.4.167.254119.4.167.2552,046
150119.4.168.0/21119.4.168.1 to 119.4.175.254119.4.175.2552,046
151119.4.176.0/21119.4.176.1 to 119.4.183.254119.4.183.2552,046
152119.4.184.0/21119.4.184.1 to 119.4.191.254119.4.191.2552,046
153119.4.192.0/21119.4.192.1 to 119.4.199.254119.4.199.2552,046
154119.4.200.0/21119.4.200.1 to 119.4.207.254119.4.207.2552,046
155119.4.208.0/21119.4.208.1 to 119.4.215.254119.4.215.2552,046
156119.4.216.0/21119.4.216.1 to 119.4.223.254119.4.223.2552,046
157119.4.224.0/21119.4.224.1 to 119.4.231.254119.4.231.2552,046
158119.4.232.0/21119.4.232.1 to 119.4.239.254119.4.239.2552,046
159119.4.240.0/21119.4.240.1 to 119.4.247.254119.4.247.2552,046
160119.4.248.0/21119.4.248.1 to 119.4.255.254119.4.255.2552,046
161119.5.0.0/21119.5.0.1 to 119.5.7.254119.5.7.2552,046
162119.5.8.0/21119.5.8.1 to 119.5.15.254119.5.15.2552,046
163119.5.16.0/21119.5.16.1 to 119.5.23.254119.5.23.2552,046
164119.5.24.0/21119.5.24.1 to 119.5.31.254119.5.31.2552,046
165119.5.32.0/21119.5.32.1 to 119.5.39.254119.5.39.2552,046
166119.5.40.0/21119.5.40.1 to 119.5.47.254119.5.47.2552,046
167119.5.48.0/21119.5.48.1 to 119.5.55.254119.5.55.2552,046
168119.5.56.0/21119.5.56.1 to 119.5.63.254119.5.63.2552,046
169119.5.64.0/21119.5.64.1 to 119.5.71.254119.5.71.2552,046
170119.5.72.0/21119.5.72.1 to 119.5.79.254119.5.79.2552,046
171119.5.80.0/21119.5.80.1 to 119.5.87.254119.5.87.2552,046
172119.5.88.0/21119.5.88.1 to 119.5.95.254119.5.95.2552,046
173119.5.96.0/21119.5.96.1 to 119.5.103.254119.5.103.2552,046
174119.5.104.0/21119.5.104.1 to 119.5.111.254119.5.111.2552,046
175119.5.112.0/21119.5.112.1 to 119.5.119.254119.5.119.2552,046
176119.5.120.0/21119.5.120.1 to 119.5.127.254119.5.127.2552,046
177119.5.128.0/21119.5.128.1 to 119.5.135.254119.5.135.2552,046
178119.5.136.0/21119.5.136.1 to 119.5.143.254119.5.143.2552,046
179119.5.144.0/21119.5.144.1 to 119.5.151.254119.5.151.2552,046
180119.5.152.0/21119.5.152.1 to 119.5.159.254119.5.159.2552,046
181119.5.160.0/21119.5.160.1 to 119.5.167.254119.5.167.2552,046
182119.5.168.0/21119.5.168.1 to 119.5.175.254119.5.175.2552,046
183119.5.176.0/21119.5.176.1 to 119.5.183.254119.5.183.2552,046
184119.5.184.0/21119.5.184.1 to 119.5.191.254119.5.191.2552,046
185119.5.192.0/21119.5.192.1 to 119.5.199.254119.5.199.2552,046
186119.5.200.0/21119.5.200.1 to 119.5.207.254119.5.207.2552,046
187119.5.208.0/21119.5.208.1 to 119.5.215.254119.5.215.2552,046
188119.5.216.0/21119.5.216.1 to 119.5.223.254119.5.223.2552,046
189119.5.224.0/21119.5.224.1 to 119.5.231.254119.5.231.2552,046
190119.5.232.0/21119.5.232.1 to 119.5.239.254119.5.239.2552,046
191119.5.240.0/21119.5.240.1 to 119.5.247.254119.5.247.2552,046
192119.5.248.0/21119.5.248.1 to 119.5.255.254119.5.255.2552,046
193119.6.0.0/21119.6.0.1 to 119.6.7.254119.6.7.2552,046
194119.6.8.0/21119.6.8.1 to 119.6.15.254119.6.15.2552,046
195119.6.16.0/21119.6.16.1 to 119.6.23.254119.6.23.2552,046
196119.6.24.0/21119.6.24.1 to 119.6.31.254119.6.31.2552,046
197119.6.32.0/21119.6.32.1 to 119.6.39.254119.6.39.2552,046
198119.6.40.0/21119.6.40.1 to 119.6.47.254119.6.47.2552,046
199119.6.48.0/21119.6.48.1 to 119.6.55.254119.6.55.2552,046
200119.6.56.0/21119.6.56.1 to 119.6.63.254119.6.63.2552,046
201119.6.64.0/21119.6.64.1 to 119.6.71.254119.6.71.2552,046
202119.6.72.0/21119.6.72.1 to 119.6.79.254119.6.79.2552,046
203119.6.80.0/21119.6.80.1 to 119.6.87.254119.6.87.2552,046
204119.6.88.0/21119.6.88.1 to 119.6.95.254119.6.95.2552,046
205119.6.96.0/21119.6.96.1 to 119.6.103.254119.6.103.2552,046
206119.6.104.0/21119.6.104.1 to 119.6.111.254119.6.111.2552,046
207119.6.112.0/21119.6.112.1 to 119.6.119.254119.6.119.2552,046
208119.6.120.0/21119.6.120.1 to 119.6.127.254119.6.127.2552,046
209119.6.128.0/21119.6.128.1 to 119.6.135.254119.6.135.2552,046
210119.6.136.0/21119.6.136.1 to 119.6.143.254119.6.143.2552,046
211119.6.144.0/21119.6.144.1 to 119.6.151.254119.6.151.2552,046
212119.6.152.0/21119.6.152.1 to 119.6.159.254119.6.159.2552,046
213119.6.160.0/21119.6.160.1 to 119.6.167.254119.6.167.2552,046
214119.6.168.0/21119.6.168.1 to 119.6.175.254119.6.175.2552,046
215119.6.176.0/21119.6.176.1 to 119.6.183.254119.6.183.2552,046
216119.6.184.0/21119.6.184.1 to 119.6.191.254119.6.191.2552,046
217119.6.192.0/21119.6.192.1 to 119.6.199.254119.6.199.2552,046
218119.6.200.0/21119.6.200.1 to 119.6.207.254119.6.207.2552,046
219119.6.208.0/21119.6.208.1 to 119.6.215.254119.6.215.2552,046
220119.6.216.0/21119.6.216.1 to 119.6.223.254119.6.223.2552,046
221119.6.224.0/21119.6.224.1 to 119.6.231.254119.6.231.2552,046
222119.6.232.0/21119.6.232.1 to 119.6.239.254119.6.239.2552,046
223119.6.240.0/21119.6.240.1 to 119.6.247.254119.6.247.2552,046
224119.6.248.0/21119.6.248.1 to 119.6.255.254119.6.255.2552,046
225119.7.0.0/21119.7.0.1 to 119.7.7.254119.7.7.2552,046
226119.7.8.0/21119.7.8.1 to 119.7.15.254119.7.15.2552,046
227119.7.16.0/21119.7.16.1 to 119.7.23.254119.7.23.2552,046
228119.7.24.0/21119.7.24.1 to 119.7.31.254119.7.31.2552,046
229119.7.32.0/21119.7.32.1 to 119.7.39.254119.7.39.2552,046
230119.7.40.0/21119.7.40.1 to 119.7.47.254119.7.47.2552,046
231119.7.48.0/21119.7.48.1 to 119.7.55.254119.7.55.2552,046
232119.7.56.0/21119.7.56.1 to 119.7.63.254119.7.63.2552,046
233119.7.64.0/21119.7.64.1 to 119.7.71.254119.7.71.2552,046
234119.7.72.0/21119.7.72.1 to 119.7.79.254119.7.79.2552,046
235119.7.80.0/21119.7.80.1 to 119.7.87.254119.7.87.2552,046
236119.7.88.0/21119.7.88.1 to 119.7.95.254119.7.95.2552,046
237119.7.96.0/21119.7.96.1 to 119.7.103.254119.7.103.2552,046
238119.7.104.0/21119.7.104.1 to 119.7.111.254119.7.111.2552,046
239119.7.112.0/21119.7.112.1 to 119.7.119.254119.7.119.2552,046
240119.7.120.0/21119.7.120.1 to 119.7.127.254119.7.127.2552,046
241119.7.128.0/21119.7.128.1 to 119.7.135.254119.7.135.2552,046
242119.7.136.0/21119.7.136.1 to 119.7.143.254119.7.143.2552,046
243119.7.144.0/21119.7.144.1 to 119.7.151.254119.7.151.2552,046
244119.7.152.0/21119.7.152.1 to 119.7.159.254119.7.159.2552,046
245119.7.160.0/21119.7.160.1 to 119.7.167.254119.7.167.2552,046
246119.7.168.0/21119.7.168.1 to 119.7.175.254119.7.175.2552,046
247119.7.176.0/21119.7.176.1 to 119.7.183.254119.7.183.2552,046
248119.7.184.0/21119.7.184.1 to 119.7.191.254119.7.191.2552,046
249119.7.192.0/21119.7.192.1 to 119.7.199.254119.7.199.2552,046
250119.7.200.0/21119.7.200.1 to 119.7.207.254119.7.207.2552,046
251119.7.208.0/21119.7.208.1 to 119.7.215.254119.7.215.2552,046
252119.7.216.0/21119.7.216.1 to 119.7.223.254119.7.223.2552,046
253119.7.224.0/21119.7.224.1 to 119.7.231.254119.7.231.2552,046
254119.7.232.0/21119.7.232.1 to 119.7.239.254119.7.239.2552,046
255119.7.240.0/21119.7.240.1 to 119.7.247.254119.7.247.2552,046
256119.7.248.0/21119.7.248.1 to 119.7.255.254119.7.255.2552,046

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.