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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.

Network111.232.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
111.232.0.0
Broadcast address
111.239.255.255
First usable
111.232.0.1
Last usable
111.239.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 6FE80000 · Integer 1877475328 to 1877999615
Reverse DNS zones
232.111.in-addr.arpa
233.111.in-addr.arpa
234.111.in-addr.arpa
235.111.in-addr.arpa
236.111.in-addr.arpa
237.111.in-addr.arpa
238.111.in-addr.arpa
239.111.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101111.11101000.00000000.00000000111.232.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01101111.11101000.00000000.00000000111.232.0.0
Broadcast01101111.11101111.11111111.11111111111.239.255.255
Split into smaller subnets/24
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

111.232.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1111.232.0.0/24111.232.0.1 to 111.232.0.254111.232.0.255254
2111.232.1.0/24111.232.1.1 to 111.232.1.254111.232.1.255254
3111.232.2.0/24111.232.2.1 to 111.232.2.254111.232.2.255254
4111.232.3.0/24111.232.3.1 to 111.232.3.254111.232.3.255254
5111.232.4.0/24111.232.4.1 to 111.232.4.254111.232.4.255254
6111.232.5.0/24111.232.5.1 to 111.232.5.254111.232.5.255254
7111.232.6.0/24111.232.6.1 to 111.232.6.254111.232.6.255254
8111.232.7.0/24111.232.7.1 to 111.232.7.254111.232.7.255254
9111.232.8.0/24111.232.8.1 to 111.232.8.254111.232.8.255254
10111.232.9.0/24111.232.9.1 to 111.232.9.254111.232.9.255254
11111.232.10.0/24111.232.10.1 to 111.232.10.254111.232.10.255254
12111.232.11.0/24111.232.11.1 to 111.232.11.254111.232.11.255254
13111.232.12.0/24111.232.12.1 to 111.232.12.254111.232.12.255254
14111.232.13.0/24111.232.13.1 to 111.232.13.254111.232.13.255254
15111.232.14.0/24111.232.14.1 to 111.232.14.254111.232.14.255254
16111.232.15.0/24111.232.15.1 to 111.232.15.254111.232.15.255254
17111.232.16.0/24111.232.16.1 to 111.232.16.254111.232.16.255254
18111.232.17.0/24111.232.17.1 to 111.232.17.254111.232.17.255254
19111.232.18.0/24111.232.18.1 to 111.232.18.254111.232.18.255254
20111.232.19.0/24111.232.19.1 to 111.232.19.254111.232.19.255254
21111.232.20.0/24111.232.20.1 to 111.232.20.254111.232.20.255254
22111.232.21.0/24111.232.21.1 to 111.232.21.254111.232.21.255254
23111.232.22.0/24111.232.22.1 to 111.232.22.254111.232.22.255254
24111.232.23.0/24111.232.23.1 to 111.232.23.254111.232.23.255254
25111.232.24.0/24111.232.24.1 to 111.232.24.254111.232.24.255254
26111.232.25.0/24111.232.25.1 to 111.232.25.254111.232.25.255254
27111.232.26.0/24111.232.26.1 to 111.232.26.254111.232.26.255254
28111.232.27.0/24111.232.27.1 to 111.232.27.254111.232.27.255254
29111.232.28.0/24111.232.28.1 to 111.232.28.254111.232.28.255254
30111.232.29.0/24111.232.29.1 to 111.232.29.254111.232.29.255254
31111.232.30.0/24111.232.30.1 to 111.232.30.254111.232.30.255254
32111.232.31.0/24111.232.31.1 to 111.232.31.254111.232.31.255254
33111.232.32.0/24111.232.32.1 to 111.232.32.254111.232.32.255254
34111.232.33.0/24111.232.33.1 to 111.232.33.254111.232.33.255254
35111.232.34.0/24111.232.34.1 to 111.232.34.254111.232.34.255254
36111.232.35.0/24111.232.35.1 to 111.232.35.254111.232.35.255254
37111.232.36.0/24111.232.36.1 to 111.232.36.254111.232.36.255254
38111.232.37.0/24111.232.37.1 to 111.232.37.254111.232.37.255254
39111.232.38.0/24111.232.38.1 to 111.232.38.254111.232.38.255254
40111.232.39.0/24111.232.39.1 to 111.232.39.254111.232.39.255254
41111.232.40.0/24111.232.40.1 to 111.232.40.254111.232.40.255254
42111.232.41.0/24111.232.41.1 to 111.232.41.254111.232.41.255254
43111.232.42.0/24111.232.42.1 to 111.232.42.254111.232.42.255254
44111.232.43.0/24111.232.43.1 to 111.232.43.254111.232.43.255254
45111.232.44.0/24111.232.44.1 to 111.232.44.254111.232.44.255254
46111.232.45.0/24111.232.45.1 to 111.232.45.254111.232.45.255254
47111.232.46.0/24111.232.46.1 to 111.232.46.254111.232.46.255254
48111.232.47.0/24111.232.47.1 to 111.232.47.254111.232.47.255254
49111.232.48.0/24111.232.48.1 to 111.232.48.254111.232.48.255254
50111.232.49.0/24111.232.49.1 to 111.232.49.254111.232.49.255254
51111.232.50.0/24111.232.50.1 to 111.232.50.254111.232.50.255254
52111.232.51.0/24111.232.51.1 to 111.232.51.254111.232.51.255254
53111.232.52.0/24111.232.52.1 to 111.232.52.254111.232.52.255254
54111.232.53.0/24111.232.53.1 to 111.232.53.254111.232.53.255254
55111.232.54.0/24111.232.54.1 to 111.232.54.254111.232.54.255254
56111.232.55.0/24111.232.55.1 to 111.232.55.254111.232.55.255254
57111.232.56.0/24111.232.56.1 to 111.232.56.254111.232.56.255254
58111.232.57.0/24111.232.57.1 to 111.232.57.254111.232.57.255254
59111.232.58.0/24111.232.58.1 to 111.232.58.254111.232.58.255254
60111.232.59.0/24111.232.59.1 to 111.232.59.254111.232.59.255254
61111.232.60.0/24111.232.60.1 to 111.232.60.254111.232.60.255254
62111.232.61.0/24111.232.61.1 to 111.232.61.254111.232.61.255254
63111.232.62.0/24111.232.62.1 to 111.232.62.254111.232.62.255254
64111.232.63.0/24111.232.63.1 to 111.232.63.254111.232.63.255254
65111.232.64.0/24111.232.64.1 to 111.232.64.254111.232.64.255254
66111.232.65.0/24111.232.65.1 to 111.232.65.254111.232.65.255254
67111.232.66.0/24111.232.66.1 to 111.232.66.254111.232.66.255254
68111.232.67.0/24111.232.67.1 to 111.232.67.254111.232.67.255254
69111.232.68.0/24111.232.68.1 to 111.232.68.254111.232.68.255254
70111.232.69.0/24111.232.69.1 to 111.232.69.254111.232.69.255254
71111.232.70.0/24111.232.70.1 to 111.232.70.254111.232.70.255254
72111.232.71.0/24111.232.71.1 to 111.232.71.254111.232.71.255254
73111.232.72.0/24111.232.72.1 to 111.232.72.254111.232.72.255254
74111.232.73.0/24111.232.73.1 to 111.232.73.254111.232.73.255254
75111.232.74.0/24111.232.74.1 to 111.232.74.254111.232.74.255254
76111.232.75.0/24111.232.75.1 to 111.232.75.254111.232.75.255254
77111.232.76.0/24111.232.76.1 to 111.232.76.254111.232.76.255254
78111.232.77.0/24111.232.77.1 to 111.232.77.254111.232.77.255254
79111.232.78.0/24111.232.78.1 to 111.232.78.254111.232.78.255254
80111.232.79.0/24111.232.79.1 to 111.232.79.254111.232.79.255254
81111.232.80.0/24111.232.80.1 to 111.232.80.254111.232.80.255254
82111.232.81.0/24111.232.81.1 to 111.232.81.254111.232.81.255254
83111.232.82.0/24111.232.82.1 to 111.232.82.254111.232.82.255254
84111.232.83.0/24111.232.83.1 to 111.232.83.254111.232.83.255254
85111.232.84.0/24111.232.84.1 to 111.232.84.254111.232.84.255254
86111.232.85.0/24111.232.85.1 to 111.232.85.254111.232.85.255254
87111.232.86.0/24111.232.86.1 to 111.232.86.254111.232.86.255254
88111.232.87.0/24111.232.87.1 to 111.232.87.254111.232.87.255254
89111.232.88.0/24111.232.88.1 to 111.232.88.254111.232.88.255254
90111.232.89.0/24111.232.89.1 to 111.232.89.254111.232.89.255254
91111.232.90.0/24111.232.90.1 to 111.232.90.254111.232.90.255254
92111.232.91.0/24111.232.91.1 to 111.232.91.254111.232.91.255254
93111.232.92.0/24111.232.92.1 to 111.232.92.254111.232.92.255254
94111.232.93.0/24111.232.93.1 to 111.232.93.254111.232.93.255254
95111.232.94.0/24111.232.94.1 to 111.232.94.254111.232.94.255254
96111.232.95.0/24111.232.95.1 to 111.232.95.254111.232.95.255254
97111.232.96.0/24111.232.96.1 to 111.232.96.254111.232.96.255254
98111.232.97.0/24111.232.97.1 to 111.232.97.254111.232.97.255254
99111.232.98.0/24111.232.98.1 to 111.232.98.254111.232.98.255254
100111.232.99.0/24111.232.99.1 to 111.232.99.254111.232.99.255254
101111.232.100.0/24111.232.100.1 to 111.232.100.254111.232.100.255254
102111.232.101.0/24111.232.101.1 to 111.232.101.254111.232.101.255254
103111.232.102.0/24111.232.102.1 to 111.232.102.254111.232.102.255254
104111.232.103.0/24111.232.103.1 to 111.232.103.254111.232.103.255254
105111.232.104.0/24111.232.104.1 to 111.232.104.254111.232.104.255254
106111.232.105.0/24111.232.105.1 to 111.232.105.254111.232.105.255254
107111.232.106.0/24111.232.106.1 to 111.232.106.254111.232.106.255254
108111.232.107.0/24111.232.107.1 to 111.232.107.254111.232.107.255254
109111.232.108.0/24111.232.108.1 to 111.232.108.254111.232.108.255254
110111.232.109.0/24111.232.109.1 to 111.232.109.254111.232.109.255254
111111.232.110.0/24111.232.110.1 to 111.232.110.254111.232.110.255254
112111.232.111.0/24111.232.111.1 to 111.232.111.254111.232.111.255254
113111.232.112.0/24111.232.112.1 to 111.232.112.254111.232.112.255254
114111.232.113.0/24111.232.113.1 to 111.232.113.254111.232.113.255254
115111.232.114.0/24111.232.114.1 to 111.232.114.254111.232.114.255254
116111.232.115.0/24111.232.115.1 to 111.232.115.254111.232.115.255254
117111.232.116.0/24111.232.116.1 to 111.232.116.254111.232.116.255254
118111.232.117.0/24111.232.117.1 to 111.232.117.254111.232.117.255254
119111.232.118.0/24111.232.118.1 to 111.232.118.254111.232.118.255254
120111.232.119.0/24111.232.119.1 to 111.232.119.254111.232.119.255254
121111.232.120.0/24111.232.120.1 to 111.232.120.254111.232.120.255254
122111.232.121.0/24111.232.121.1 to 111.232.121.254111.232.121.255254
123111.232.122.0/24111.232.122.1 to 111.232.122.254111.232.122.255254
124111.232.123.0/24111.232.123.1 to 111.232.123.254111.232.123.255254
125111.232.124.0/24111.232.124.1 to 111.232.124.254111.232.124.255254
126111.232.125.0/24111.232.125.1 to 111.232.125.254111.232.125.255254
127111.232.126.0/24111.232.126.1 to 111.232.126.254111.232.126.255254
128111.232.127.0/24111.232.127.1 to 111.232.127.254111.232.127.255254
129111.232.128.0/24111.232.128.1 to 111.232.128.254111.232.128.255254
130111.232.129.0/24111.232.129.1 to 111.232.129.254111.232.129.255254
131111.232.130.0/24111.232.130.1 to 111.232.130.254111.232.130.255254
132111.232.131.0/24111.232.131.1 to 111.232.131.254111.232.131.255254
133111.232.132.0/24111.232.132.1 to 111.232.132.254111.232.132.255254
134111.232.133.0/24111.232.133.1 to 111.232.133.254111.232.133.255254
135111.232.134.0/24111.232.134.1 to 111.232.134.254111.232.134.255254
136111.232.135.0/24111.232.135.1 to 111.232.135.254111.232.135.255254
137111.232.136.0/24111.232.136.1 to 111.232.136.254111.232.136.255254
138111.232.137.0/24111.232.137.1 to 111.232.137.254111.232.137.255254
139111.232.138.0/24111.232.138.1 to 111.232.138.254111.232.138.255254
140111.232.139.0/24111.232.139.1 to 111.232.139.254111.232.139.255254
141111.232.140.0/24111.232.140.1 to 111.232.140.254111.232.140.255254
142111.232.141.0/24111.232.141.1 to 111.232.141.254111.232.141.255254
143111.232.142.0/24111.232.142.1 to 111.232.142.254111.232.142.255254
144111.232.143.0/24111.232.143.1 to 111.232.143.254111.232.143.255254
145111.232.144.0/24111.232.144.1 to 111.232.144.254111.232.144.255254
146111.232.145.0/24111.232.145.1 to 111.232.145.254111.232.145.255254
147111.232.146.0/24111.232.146.1 to 111.232.146.254111.232.146.255254
148111.232.147.0/24111.232.147.1 to 111.232.147.254111.232.147.255254
149111.232.148.0/24111.232.148.1 to 111.232.148.254111.232.148.255254
150111.232.149.0/24111.232.149.1 to 111.232.149.254111.232.149.255254
151111.232.150.0/24111.232.150.1 to 111.232.150.254111.232.150.255254
152111.232.151.0/24111.232.151.1 to 111.232.151.254111.232.151.255254
153111.232.152.0/24111.232.152.1 to 111.232.152.254111.232.152.255254
154111.232.153.0/24111.232.153.1 to 111.232.153.254111.232.153.255254
155111.232.154.0/24111.232.154.1 to 111.232.154.254111.232.154.255254
156111.232.155.0/24111.232.155.1 to 111.232.155.254111.232.155.255254
157111.232.156.0/24111.232.156.1 to 111.232.156.254111.232.156.255254
158111.232.157.0/24111.232.157.1 to 111.232.157.254111.232.157.255254
159111.232.158.0/24111.232.158.1 to 111.232.158.254111.232.158.255254
160111.232.159.0/24111.232.159.1 to 111.232.159.254111.232.159.255254
161111.232.160.0/24111.232.160.1 to 111.232.160.254111.232.160.255254
162111.232.161.0/24111.232.161.1 to 111.232.161.254111.232.161.255254
163111.232.162.0/24111.232.162.1 to 111.232.162.254111.232.162.255254
164111.232.163.0/24111.232.163.1 to 111.232.163.254111.232.163.255254
165111.232.164.0/24111.232.164.1 to 111.232.164.254111.232.164.255254
166111.232.165.0/24111.232.165.1 to 111.232.165.254111.232.165.255254
167111.232.166.0/24111.232.166.1 to 111.232.166.254111.232.166.255254
168111.232.167.0/24111.232.167.1 to 111.232.167.254111.232.167.255254
169111.232.168.0/24111.232.168.1 to 111.232.168.254111.232.168.255254
170111.232.169.0/24111.232.169.1 to 111.232.169.254111.232.169.255254
171111.232.170.0/24111.232.170.1 to 111.232.170.254111.232.170.255254
172111.232.171.0/24111.232.171.1 to 111.232.171.254111.232.171.255254
173111.232.172.0/24111.232.172.1 to 111.232.172.254111.232.172.255254
174111.232.173.0/24111.232.173.1 to 111.232.173.254111.232.173.255254
175111.232.174.0/24111.232.174.1 to 111.232.174.254111.232.174.255254
176111.232.175.0/24111.232.175.1 to 111.232.175.254111.232.175.255254
177111.232.176.0/24111.232.176.1 to 111.232.176.254111.232.176.255254
178111.232.177.0/24111.232.177.1 to 111.232.177.254111.232.177.255254
179111.232.178.0/24111.232.178.1 to 111.232.178.254111.232.178.255254
180111.232.179.0/24111.232.179.1 to 111.232.179.254111.232.179.255254
181111.232.180.0/24111.232.180.1 to 111.232.180.254111.232.180.255254
182111.232.181.0/24111.232.181.1 to 111.232.181.254111.232.181.255254
183111.232.182.0/24111.232.182.1 to 111.232.182.254111.232.182.255254
184111.232.183.0/24111.232.183.1 to 111.232.183.254111.232.183.255254
185111.232.184.0/24111.232.184.1 to 111.232.184.254111.232.184.255254
186111.232.185.0/24111.232.185.1 to 111.232.185.254111.232.185.255254
187111.232.186.0/24111.232.186.1 to 111.232.186.254111.232.186.255254
188111.232.187.0/24111.232.187.1 to 111.232.187.254111.232.187.255254
189111.232.188.0/24111.232.188.1 to 111.232.188.254111.232.188.255254
190111.232.189.0/24111.232.189.1 to 111.232.189.254111.232.189.255254
191111.232.190.0/24111.232.190.1 to 111.232.190.254111.232.190.255254
192111.232.191.0/24111.232.191.1 to 111.232.191.254111.232.191.255254
193111.232.192.0/24111.232.192.1 to 111.232.192.254111.232.192.255254
194111.232.193.0/24111.232.193.1 to 111.232.193.254111.232.193.255254
195111.232.194.0/24111.232.194.1 to 111.232.194.254111.232.194.255254
196111.232.195.0/24111.232.195.1 to 111.232.195.254111.232.195.255254
197111.232.196.0/24111.232.196.1 to 111.232.196.254111.232.196.255254
198111.232.197.0/24111.232.197.1 to 111.232.197.254111.232.197.255254
199111.232.198.0/24111.232.198.1 to 111.232.198.254111.232.198.255254
200111.232.199.0/24111.232.199.1 to 111.232.199.254111.232.199.255254
201111.232.200.0/24111.232.200.1 to 111.232.200.254111.232.200.255254
202111.232.201.0/24111.232.201.1 to 111.232.201.254111.232.201.255254
203111.232.202.0/24111.232.202.1 to 111.232.202.254111.232.202.255254
204111.232.203.0/24111.232.203.1 to 111.232.203.254111.232.203.255254
205111.232.204.0/24111.232.204.1 to 111.232.204.254111.232.204.255254
206111.232.205.0/24111.232.205.1 to 111.232.205.254111.232.205.255254
207111.232.206.0/24111.232.206.1 to 111.232.206.254111.232.206.255254
208111.232.207.0/24111.232.207.1 to 111.232.207.254111.232.207.255254
209111.232.208.0/24111.232.208.1 to 111.232.208.254111.232.208.255254
210111.232.209.0/24111.232.209.1 to 111.232.209.254111.232.209.255254
211111.232.210.0/24111.232.210.1 to 111.232.210.254111.232.210.255254
212111.232.211.0/24111.232.211.1 to 111.232.211.254111.232.211.255254
213111.232.212.0/24111.232.212.1 to 111.232.212.254111.232.212.255254
214111.232.213.0/24111.232.213.1 to 111.232.213.254111.232.213.255254
215111.232.214.0/24111.232.214.1 to 111.232.214.254111.232.214.255254
216111.232.215.0/24111.232.215.1 to 111.232.215.254111.232.215.255254
217111.232.216.0/24111.232.216.1 to 111.232.216.254111.232.216.255254
218111.232.217.0/24111.232.217.1 to 111.232.217.254111.232.217.255254
219111.232.218.0/24111.232.218.1 to 111.232.218.254111.232.218.255254
220111.232.219.0/24111.232.219.1 to 111.232.219.254111.232.219.255254
221111.232.220.0/24111.232.220.1 to 111.232.220.254111.232.220.255254
222111.232.221.0/24111.232.221.1 to 111.232.221.254111.232.221.255254
223111.232.222.0/24111.232.222.1 to 111.232.222.254111.232.222.255254
224111.232.223.0/24111.232.223.1 to 111.232.223.254111.232.223.255254
225111.232.224.0/24111.232.224.1 to 111.232.224.254111.232.224.255254
226111.232.225.0/24111.232.225.1 to 111.232.225.254111.232.225.255254
227111.232.226.0/24111.232.226.1 to 111.232.226.254111.232.226.255254
228111.232.227.0/24111.232.227.1 to 111.232.227.254111.232.227.255254
229111.232.228.0/24111.232.228.1 to 111.232.228.254111.232.228.255254
230111.232.229.0/24111.232.229.1 to 111.232.229.254111.232.229.255254
231111.232.230.0/24111.232.230.1 to 111.232.230.254111.232.230.255254
232111.232.231.0/24111.232.231.1 to 111.232.231.254111.232.231.255254
233111.232.232.0/24111.232.232.1 to 111.232.232.254111.232.232.255254
234111.232.233.0/24111.232.233.1 to 111.232.233.254111.232.233.255254
235111.232.234.0/24111.232.234.1 to 111.232.234.254111.232.234.255254
236111.232.235.0/24111.232.235.1 to 111.232.235.254111.232.235.255254
237111.232.236.0/24111.232.236.1 to 111.232.236.254111.232.236.255254
238111.232.237.0/24111.232.237.1 to 111.232.237.254111.232.237.255254
239111.232.238.0/24111.232.238.1 to 111.232.238.254111.232.238.255254
240111.232.239.0/24111.232.239.1 to 111.232.239.254111.232.239.255254
241111.232.240.0/24111.232.240.1 to 111.232.240.254111.232.240.255254
242111.232.241.0/24111.232.241.1 to 111.232.241.254111.232.241.255254
243111.232.242.0/24111.232.242.1 to 111.232.242.254111.232.242.255254
244111.232.243.0/24111.232.243.1 to 111.232.243.254111.232.243.255254
245111.232.244.0/24111.232.244.1 to 111.232.244.254111.232.244.255254
246111.232.245.0/24111.232.245.1 to 111.232.245.254111.232.245.255254
247111.232.246.0/24111.232.246.1 to 111.232.246.254111.232.246.255254
248111.232.247.0/24111.232.247.1 to 111.232.247.254111.232.247.255254
249111.232.248.0/24111.232.248.1 to 111.232.248.254111.232.248.255254
250111.232.249.0/24111.232.249.1 to 111.232.249.254111.232.249.255254
251111.232.250.0/24111.232.250.1 to 111.232.250.254111.232.250.255254
252111.232.251.0/24111.232.251.1 to 111.232.251.254111.232.251.255254
253111.232.252.0/24111.232.252.1 to 111.232.252.254111.232.252.255254
254111.232.253.0/24111.232.253.1 to 111.232.253.254111.232.253.255254
255111.232.254.0/24111.232.254.1 to 111.232.254.254111.232.254.255254
256111.232.255.0/24111.232.255.1 to 111.232.255.254111.232.255.255254

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.