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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.

Network119.96.0.0/12
Usable hosts1,048,574
Subnet mask255.240.0.0
Addresses1,048,576
Network address
119.96.0.0
Broadcast address
119.111.255.255
First usable
119.96.0.1
Last usable
119.111.255.254
Usable hosts
1,048,574 (1,048,576 less the network and broadcast addresses)
Subnet mask
255.240.0.0
Wildcard mask
0.15.255.255 (Cisco ACLs, OSPF)
Prefix length
/12
Type
Public public
Old class
A (default /8)
As numbers
Hex 77600000 · Integer 2002780160 to 2003828735
Reverse DNS zones
96.119.in-addr.arpa
97.119.in-addr.arpa
98.119.in-addr.arpa
99.119.in-addr.arpa
100.119.in-addr.arpa
101.119.in-addr.arpa
102.119.in-addr.arpa
103.119.in-addr.arpa
104.119.in-addr.arpa
105.119.in-addr.arpa
106.119.in-addr.arpa
107.119.in-addr.arpa
108.119.in-addr.arpa
109.119.in-addr.arpa
110.119.in-addr.arpa
111.119.in-addr.arpa
/12 is not on a 8-bit boundary, so it takes 16 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110111.01100000.00000000.00000000119.96.0.0
Subnet mask11111111.11110000.00000000.00000000255.240.0.0
Network01110111.01100000.00000000.00000000119.96.0.0
Broadcast01110111.01101111.11111111.11111111119.111.255.255
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/17 (32)/18 (64)/19 (128)/20 (256)/21 (512)/22 (1,024)/23 (2,048)/24 (4,096)

119.96.0.0/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1119.96.0.0/24119.96.0.1 to 119.96.0.254119.96.0.255254
2119.96.1.0/24119.96.1.1 to 119.96.1.254119.96.1.255254
3119.96.2.0/24119.96.2.1 to 119.96.2.254119.96.2.255254
4119.96.3.0/24119.96.3.1 to 119.96.3.254119.96.3.255254
5119.96.4.0/24119.96.4.1 to 119.96.4.254119.96.4.255254
6119.96.5.0/24119.96.5.1 to 119.96.5.254119.96.5.255254
7119.96.6.0/24119.96.6.1 to 119.96.6.254119.96.6.255254
8119.96.7.0/24119.96.7.1 to 119.96.7.254119.96.7.255254
9119.96.8.0/24119.96.8.1 to 119.96.8.254119.96.8.255254
10119.96.9.0/24119.96.9.1 to 119.96.9.254119.96.9.255254
11119.96.10.0/24119.96.10.1 to 119.96.10.254119.96.10.255254
12119.96.11.0/24119.96.11.1 to 119.96.11.254119.96.11.255254
13119.96.12.0/24119.96.12.1 to 119.96.12.254119.96.12.255254
14119.96.13.0/24119.96.13.1 to 119.96.13.254119.96.13.255254
15119.96.14.0/24119.96.14.1 to 119.96.14.254119.96.14.255254
16119.96.15.0/24119.96.15.1 to 119.96.15.254119.96.15.255254
17119.96.16.0/24119.96.16.1 to 119.96.16.254119.96.16.255254
18119.96.17.0/24119.96.17.1 to 119.96.17.254119.96.17.255254
19119.96.18.0/24119.96.18.1 to 119.96.18.254119.96.18.255254
20119.96.19.0/24119.96.19.1 to 119.96.19.254119.96.19.255254
21119.96.20.0/24119.96.20.1 to 119.96.20.254119.96.20.255254
22119.96.21.0/24119.96.21.1 to 119.96.21.254119.96.21.255254
23119.96.22.0/24119.96.22.1 to 119.96.22.254119.96.22.255254
24119.96.23.0/24119.96.23.1 to 119.96.23.254119.96.23.255254
25119.96.24.0/24119.96.24.1 to 119.96.24.254119.96.24.255254
26119.96.25.0/24119.96.25.1 to 119.96.25.254119.96.25.255254
27119.96.26.0/24119.96.26.1 to 119.96.26.254119.96.26.255254
28119.96.27.0/24119.96.27.1 to 119.96.27.254119.96.27.255254
29119.96.28.0/24119.96.28.1 to 119.96.28.254119.96.28.255254
30119.96.29.0/24119.96.29.1 to 119.96.29.254119.96.29.255254
31119.96.30.0/24119.96.30.1 to 119.96.30.254119.96.30.255254
32119.96.31.0/24119.96.31.1 to 119.96.31.254119.96.31.255254
33119.96.32.0/24119.96.32.1 to 119.96.32.254119.96.32.255254
34119.96.33.0/24119.96.33.1 to 119.96.33.254119.96.33.255254
35119.96.34.0/24119.96.34.1 to 119.96.34.254119.96.34.255254
36119.96.35.0/24119.96.35.1 to 119.96.35.254119.96.35.255254
37119.96.36.0/24119.96.36.1 to 119.96.36.254119.96.36.255254
38119.96.37.0/24119.96.37.1 to 119.96.37.254119.96.37.255254
39119.96.38.0/24119.96.38.1 to 119.96.38.254119.96.38.255254
40119.96.39.0/24119.96.39.1 to 119.96.39.254119.96.39.255254
41119.96.40.0/24119.96.40.1 to 119.96.40.254119.96.40.255254
42119.96.41.0/24119.96.41.1 to 119.96.41.254119.96.41.255254
43119.96.42.0/24119.96.42.1 to 119.96.42.254119.96.42.255254
44119.96.43.0/24119.96.43.1 to 119.96.43.254119.96.43.255254
45119.96.44.0/24119.96.44.1 to 119.96.44.254119.96.44.255254
46119.96.45.0/24119.96.45.1 to 119.96.45.254119.96.45.255254
47119.96.46.0/24119.96.46.1 to 119.96.46.254119.96.46.255254
48119.96.47.0/24119.96.47.1 to 119.96.47.254119.96.47.255254
49119.96.48.0/24119.96.48.1 to 119.96.48.254119.96.48.255254
50119.96.49.0/24119.96.49.1 to 119.96.49.254119.96.49.255254
51119.96.50.0/24119.96.50.1 to 119.96.50.254119.96.50.255254
52119.96.51.0/24119.96.51.1 to 119.96.51.254119.96.51.255254
53119.96.52.0/24119.96.52.1 to 119.96.52.254119.96.52.255254
54119.96.53.0/24119.96.53.1 to 119.96.53.254119.96.53.255254
55119.96.54.0/24119.96.54.1 to 119.96.54.254119.96.54.255254
56119.96.55.0/24119.96.55.1 to 119.96.55.254119.96.55.255254
57119.96.56.0/24119.96.56.1 to 119.96.56.254119.96.56.255254
58119.96.57.0/24119.96.57.1 to 119.96.57.254119.96.57.255254
59119.96.58.0/24119.96.58.1 to 119.96.58.254119.96.58.255254
60119.96.59.0/24119.96.59.1 to 119.96.59.254119.96.59.255254
61119.96.60.0/24119.96.60.1 to 119.96.60.254119.96.60.255254
62119.96.61.0/24119.96.61.1 to 119.96.61.254119.96.61.255254
63119.96.62.0/24119.96.62.1 to 119.96.62.254119.96.62.255254
64119.96.63.0/24119.96.63.1 to 119.96.63.254119.96.63.255254
65119.96.64.0/24119.96.64.1 to 119.96.64.254119.96.64.255254
66119.96.65.0/24119.96.65.1 to 119.96.65.254119.96.65.255254
67119.96.66.0/24119.96.66.1 to 119.96.66.254119.96.66.255254
68119.96.67.0/24119.96.67.1 to 119.96.67.254119.96.67.255254
69119.96.68.0/24119.96.68.1 to 119.96.68.254119.96.68.255254
70119.96.69.0/24119.96.69.1 to 119.96.69.254119.96.69.255254
71119.96.70.0/24119.96.70.1 to 119.96.70.254119.96.70.255254
72119.96.71.0/24119.96.71.1 to 119.96.71.254119.96.71.255254
73119.96.72.0/24119.96.72.1 to 119.96.72.254119.96.72.255254
74119.96.73.0/24119.96.73.1 to 119.96.73.254119.96.73.255254
75119.96.74.0/24119.96.74.1 to 119.96.74.254119.96.74.255254
76119.96.75.0/24119.96.75.1 to 119.96.75.254119.96.75.255254
77119.96.76.0/24119.96.76.1 to 119.96.76.254119.96.76.255254
78119.96.77.0/24119.96.77.1 to 119.96.77.254119.96.77.255254
79119.96.78.0/24119.96.78.1 to 119.96.78.254119.96.78.255254
80119.96.79.0/24119.96.79.1 to 119.96.79.254119.96.79.255254
81119.96.80.0/24119.96.80.1 to 119.96.80.254119.96.80.255254
82119.96.81.0/24119.96.81.1 to 119.96.81.254119.96.81.255254
83119.96.82.0/24119.96.82.1 to 119.96.82.254119.96.82.255254
84119.96.83.0/24119.96.83.1 to 119.96.83.254119.96.83.255254
85119.96.84.0/24119.96.84.1 to 119.96.84.254119.96.84.255254
86119.96.85.0/24119.96.85.1 to 119.96.85.254119.96.85.255254
87119.96.86.0/24119.96.86.1 to 119.96.86.254119.96.86.255254
88119.96.87.0/24119.96.87.1 to 119.96.87.254119.96.87.255254
89119.96.88.0/24119.96.88.1 to 119.96.88.254119.96.88.255254
90119.96.89.0/24119.96.89.1 to 119.96.89.254119.96.89.255254
91119.96.90.0/24119.96.90.1 to 119.96.90.254119.96.90.255254
92119.96.91.0/24119.96.91.1 to 119.96.91.254119.96.91.255254
93119.96.92.0/24119.96.92.1 to 119.96.92.254119.96.92.255254
94119.96.93.0/24119.96.93.1 to 119.96.93.254119.96.93.255254
95119.96.94.0/24119.96.94.1 to 119.96.94.254119.96.94.255254
96119.96.95.0/24119.96.95.1 to 119.96.95.254119.96.95.255254
97119.96.96.0/24119.96.96.1 to 119.96.96.254119.96.96.255254
98119.96.97.0/24119.96.97.1 to 119.96.97.254119.96.97.255254
99119.96.98.0/24119.96.98.1 to 119.96.98.254119.96.98.255254
100119.96.99.0/24119.96.99.1 to 119.96.99.254119.96.99.255254
101119.96.100.0/24119.96.100.1 to 119.96.100.254119.96.100.255254
102119.96.101.0/24119.96.101.1 to 119.96.101.254119.96.101.255254
103119.96.102.0/24119.96.102.1 to 119.96.102.254119.96.102.255254
104119.96.103.0/24119.96.103.1 to 119.96.103.254119.96.103.255254
105119.96.104.0/24119.96.104.1 to 119.96.104.254119.96.104.255254
106119.96.105.0/24119.96.105.1 to 119.96.105.254119.96.105.255254
107119.96.106.0/24119.96.106.1 to 119.96.106.254119.96.106.255254
108119.96.107.0/24119.96.107.1 to 119.96.107.254119.96.107.255254
109119.96.108.0/24119.96.108.1 to 119.96.108.254119.96.108.255254
110119.96.109.0/24119.96.109.1 to 119.96.109.254119.96.109.255254
111119.96.110.0/24119.96.110.1 to 119.96.110.254119.96.110.255254
112119.96.111.0/24119.96.111.1 to 119.96.111.254119.96.111.255254
113119.96.112.0/24119.96.112.1 to 119.96.112.254119.96.112.255254
114119.96.113.0/24119.96.113.1 to 119.96.113.254119.96.113.255254
115119.96.114.0/24119.96.114.1 to 119.96.114.254119.96.114.255254
116119.96.115.0/24119.96.115.1 to 119.96.115.254119.96.115.255254
117119.96.116.0/24119.96.116.1 to 119.96.116.254119.96.116.255254
118119.96.117.0/24119.96.117.1 to 119.96.117.254119.96.117.255254
119119.96.118.0/24119.96.118.1 to 119.96.118.254119.96.118.255254
120119.96.119.0/24119.96.119.1 to 119.96.119.254119.96.119.255254
121119.96.120.0/24119.96.120.1 to 119.96.120.254119.96.120.255254
122119.96.121.0/24119.96.121.1 to 119.96.121.254119.96.121.255254
123119.96.122.0/24119.96.122.1 to 119.96.122.254119.96.122.255254
124119.96.123.0/24119.96.123.1 to 119.96.123.254119.96.123.255254
125119.96.124.0/24119.96.124.1 to 119.96.124.254119.96.124.255254
126119.96.125.0/24119.96.125.1 to 119.96.125.254119.96.125.255254
127119.96.126.0/24119.96.126.1 to 119.96.126.254119.96.126.255254
128119.96.127.0/24119.96.127.1 to 119.96.127.254119.96.127.255254
129119.96.128.0/24119.96.128.1 to 119.96.128.254119.96.128.255254
130119.96.129.0/24119.96.129.1 to 119.96.129.254119.96.129.255254
131119.96.130.0/24119.96.130.1 to 119.96.130.254119.96.130.255254
132119.96.131.0/24119.96.131.1 to 119.96.131.254119.96.131.255254
133119.96.132.0/24119.96.132.1 to 119.96.132.254119.96.132.255254
134119.96.133.0/24119.96.133.1 to 119.96.133.254119.96.133.255254
135119.96.134.0/24119.96.134.1 to 119.96.134.254119.96.134.255254
136119.96.135.0/24119.96.135.1 to 119.96.135.254119.96.135.255254
137119.96.136.0/24119.96.136.1 to 119.96.136.254119.96.136.255254
138119.96.137.0/24119.96.137.1 to 119.96.137.254119.96.137.255254
139119.96.138.0/24119.96.138.1 to 119.96.138.254119.96.138.255254
140119.96.139.0/24119.96.139.1 to 119.96.139.254119.96.139.255254
141119.96.140.0/24119.96.140.1 to 119.96.140.254119.96.140.255254
142119.96.141.0/24119.96.141.1 to 119.96.141.254119.96.141.255254
143119.96.142.0/24119.96.142.1 to 119.96.142.254119.96.142.255254
144119.96.143.0/24119.96.143.1 to 119.96.143.254119.96.143.255254
145119.96.144.0/24119.96.144.1 to 119.96.144.254119.96.144.255254
146119.96.145.0/24119.96.145.1 to 119.96.145.254119.96.145.255254
147119.96.146.0/24119.96.146.1 to 119.96.146.254119.96.146.255254
148119.96.147.0/24119.96.147.1 to 119.96.147.254119.96.147.255254
149119.96.148.0/24119.96.148.1 to 119.96.148.254119.96.148.255254
150119.96.149.0/24119.96.149.1 to 119.96.149.254119.96.149.255254
151119.96.150.0/24119.96.150.1 to 119.96.150.254119.96.150.255254
152119.96.151.0/24119.96.151.1 to 119.96.151.254119.96.151.255254
153119.96.152.0/24119.96.152.1 to 119.96.152.254119.96.152.255254
154119.96.153.0/24119.96.153.1 to 119.96.153.254119.96.153.255254
155119.96.154.0/24119.96.154.1 to 119.96.154.254119.96.154.255254
156119.96.155.0/24119.96.155.1 to 119.96.155.254119.96.155.255254
157119.96.156.0/24119.96.156.1 to 119.96.156.254119.96.156.255254
158119.96.157.0/24119.96.157.1 to 119.96.157.254119.96.157.255254
159119.96.158.0/24119.96.158.1 to 119.96.158.254119.96.158.255254
160119.96.159.0/24119.96.159.1 to 119.96.159.254119.96.159.255254
161119.96.160.0/24119.96.160.1 to 119.96.160.254119.96.160.255254
162119.96.161.0/24119.96.161.1 to 119.96.161.254119.96.161.255254
163119.96.162.0/24119.96.162.1 to 119.96.162.254119.96.162.255254
164119.96.163.0/24119.96.163.1 to 119.96.163.254119.96.163.255254
165119.96.164.0/24119.96.164.1 to 119.96.164.254119.96.164.255254
166119.96.165.0/24119.96.165.1 to 119.96.165.254119.96.165.255254
167119.96.166.0/24119.96.166.1 to 119.96.166.254119.96.166.255254
168119.96.167.0/24119.96.167.1 to 119.96.167.254119.96.167.255254
169119.96.168.0/24119.96.168.1 to 119.96.168.254119.96.168.255254
170119.96.169.0/24119.96.169.1 to 119.96.169.254119.96.169.255254
171119.96.170.0/24119.96.170.1 to 119.96.170.254119.96.170.255254
172119.96.171.0/24119.96.171.1 to 119.96.171.254119.96.171.255254
173119.96.172.0/24119.96.172.1 to 119.96.172.254119.96.172.255254
174119.96.173.0/24119.96.173.1 to 119.96.173.254119.96.173.255254
175119.96.174.0/24119.96.174.1 to 119.96.174.254119.96.174.255254
176119.96.175.0/24119.96.175.1 to 119.96.175.254119.96.175.255254
177119.96.176.0/24119.96.176.1 to 119.96.176.254119.96.176.255254
178119.96.177.0/24119.96.177.1 to 119.96.177.254119.96.177.255254
179119.96.178.0/24119.96.178.1 to 119.96.178.254119.96.178.255254
180119.96.179.0/24119.96.179.1 to 119.96.179.254119.96.179.255254
181119.96.180.0/24119.96.180.1 to 119.96.180.254119.96.180.255254
182119.96.181.0/24119.96.181.1 to 119.96.181.254119.96.181.255254
183119.96.182.0/24119.96.182.1 to 119.96.182.254119.96.182.255254
184119.96.183.0/24119.96.183.1 to 119.96.183.254119.96.183.255254
185119.96.184.0/24119.96.184.1 to 119.96.184.254119.96.184.255254
186119.96.185.0/24119.96.185.1 to 119.96.185.254119.96.185.255254
187119.96.186.0/24119.96.186.1 to 119.96.186.254119.96.186.255254
188119.96.187.0/24119.96.187.1 to 119.96.187.254119.96.187.255254
189119.96.188.0/24119.96.188.1 to 119.96.188.254119.96.188.255254
190119.96.189.0/24119.96.189.1 to 119.96.189.254119.96.189.255254
191119.96.190.0/24119.96.190.1 to 119.96.190.254119.96.190.255254
192119.96.191.0/24119.96.191.1 to 119.96.191.254119.96.191.255254
193119.96.192.0/24119.96.192.1 to 119.96.192.254119.96.192.255254
194119.96.193.0/24119.96.193.1 to 119.96.193.254119.96.193.255254
195119.96.194.0/24119.96.194.1 to 119.96.194.254119.96.194.255254
196119.96.195.0/24119.96.195.1 to 119.96.195.254119.96.195.255254
197119.96.196.0/24119.96.196.1 to 119.96.196.254119.96.196.255254
198119.96.197.0/24119.96.197.1 to 119.96.197.254119.96.197.255254
199119.96.198.0/24119.96.198.1 to 119.96.198.254119.96.198.255254
200119.96.199.0/24119.96.199.1 to 119.96.199.254119.96.199.255254
201119.96.200.0/24119.96.200.1 to 119.96.200.254119.96.200.255254
202119.96.201.0/24119.96.201.1 to 119.96.201.254119.96.201.255254
203119.96.202.0/24119.96.202.1 to 119.96.202.254119.96.202.255254
204119.96.203.0/24119.96.203.1 to 119.96.203.254119.96.203.255254
205119.96.204.0/24119.96.204.1 to 119.96.204.254119.96.204.255254
206119.96.205.0/24119.96.205.1 to 119.96.205.254119.96.205.255254
207119.96.206.0/24119.96.206.1 to 119.96.206.254119.96.206.255254
208119.96.207.0/24119.96.207.1 to 119.96.207.254119.96.207.255254
209119.96.208.0/24119.96.208.1 to 119.96.208.254119.96.208.255254
210119.96.209.0/24119.96.209.1 to 119.96.209.254119.96.209.255254
211119.96.210.0/24119.96.210.1 to 119.96.210.254119.96.210.255254
212119.96.211.0/24119.96.211.1 to 119.96.211.254119.96.211.255254
213119.96.212.0/24119.96.212.1 to 119.96.212.254119.96.212.255254
214119.96.213.0/24119.96.213.1 to 119.96.213.254119.96.213.255254
215119.96.214.0/24119.96.214.1 to 119.96.214.254119.96.214.255254
216119.96.215.0/24119.96.215.1 to 119.96.215.254119.96.215.255254
217119.96.216.0/24119.96.216.1 to 119.96.216.254119.96.216.255254
218119.96.217.0/24119.96.217.1 to 119.96.217.254119.96.217.255254
219119.96.218.0/24119.96.218.1 to 119.96.218.254119.96.218.255254
220119.96.219.0/24119.96.219.1 to 119.96.219.254119.96.219.255254
221119.96.220.0/24119.96.220.1 to 119.96.220.254119.96.220.255254
222119.96.221.0/24119.96.221.1 to 119.96.221.254119.96.221.255254
223119.96.222.0/24119.96.222.1 to 119.96.222.254119.96.222.255254
224119.96.223.0/24119.96.223.1 to 119.96.223.254119.96.223.255254
225119.96.224.0/24119.96.224.1 to 119.96.224.254119.96.224.255254
226119.96.225.0/24119.96.225.1 to 119.96.225.254119.96.225.255254
227119.96.226.0/24119.96.226.1 to 119.96.226.254119.96.226.255254
228119.96.227.0/24119.96.227.1 to 119.96.227.254119.96.227.255254
229119.96.228.0/24119.96.228.1 to 119.96.228.254119.96.228.255254
230119.96.229.0/24119.96.229.1 to 119.96.229.254119.96.229.255254
231119.96.230.0/24119.96.230.1 to 119.96.230.254119.96.230.255254
232119.96.231.0/24119.96.231.1 to 119.96.231.254119.96.231.255254
233119.96.232.0/24119.96.232.1 to 119.96.232.254119.96.232.255254
234119.96.233.0/24119.96.233.1 to 119.96.233.254119.96.233.255254
235119.96.234.0/24119.96.234.1 to 119.96.234.254119.96.234.255254
236119.96.235.0/24119.96.235.1 to 119.96.235.254119.96.235.255254
237119.96.236.0/24119.96.236.1 to 119.96.236.254119.96.236.255254
238119.96.237.0/24119.96.237.1 to 119.96.237.254119.96.237.255254
239119.96.238.0/24119.96.238.1 to 119.96.238.254119.96.238.255254
240119.96.239.0/24119.96.239.1 to 119.96.239.254119.96.239.255254
241119.96.240.0/24119.96.240.1 to 119.96.240.254119.96.240.255254
242119.96.241.0/24119.96.241.1 to 119.96.241.254119.96.241.255254
243119.96.242.0/24119.96.242.1 to 119.96.242.254119.96.242.255254
244119.96.243.0/24119.96.243.1 to 119.96.243.254119.96.243.255254
245119.96.244.0/24119.96.244.1 to 119.96.244.254119.96.244.255254
246119.96.245.0/24119.96.245.1 to 119.96.245.254119.96.245.255254
247119.96.246.0/24119.96.246.1 to 119.96.246.254119.96.246.255254
248119.96.247.0/24119.96.247.1 to 119.96.247.254119.96.247.255254
249119.96.248.0/24119.96.248.1 to 119.96.248.254119.96.248.255254
250119.96.249.0/24119.96.249.1 to 119.96.249.254119.96.249.255254
251119.96.250.0/24119.96.250.1 to 119.96.250.254119.96.250.255254
252119.96.251.0/24119.96.251.1 to 119.96.251.254119.96.251.255254
253119.96.252.0/24119.96.252.1 to 119.96.252.254119.96.252.255254
254119.96.253.0/24119.96.253.1 to 119.96.253.254119.96.253.255254
255119.96.254.0/24119.96.254.1 to 119.96.254.254119.96.254.255254
256119.96.255.0/24119.96.255.1 to 119.96.255.254119.96.255.255254

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.