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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.

Network210.232.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
210.232.0.0
Broadcast address
210.239.255.255
First usable
210.232.0.1
Last usable
210.239.255.254
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
C (default /24)
As numbers
Hex D2E80000 · Integer 3538419712 to 3538943999
Reverse DNS zones
232.210.in-addr.arpa
233.210.in-addr.arpa
234.210.in-addr.arpa
235.210.in-addr.arpa
236.210.in-addr.arpa
237.210.in-addr.arpa
238.210.in-addr.arpa
239.210.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
Address11010010.11101000.00000000.00000000210.232.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11010010.11101000.00000000.00000000210.232.0.0
Broadcast11010010.11101111.11111111.11111111210.239.255.255
Split into smaller subnets/22
/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)

210.232.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1210.232.0.0/22210.232.0.1 to 210.232.3.254210.232.3.2551,022
2210.232.4.0/22210.232.4.1 to 210.232.7.254210.232.7.2551,022
3210.232.8.0/22210.232.8.1 to 210.232.11.254210.232.11.2551,022
4210.232.12.0/22210.232.12.1 to 210.232.15.254210.232.15.2551,022
5210.232.16.0/22210.232.16.1 to 210.232.19.254210.232.19.2551,022
6210.232.20.0/22210.232.20.1 to 210.232.23.254210.232.23.2551,022
7210.232.24.0/22210.232.24.1 to 210.232.27.254210.232.27.2551,022
8210.232.28.0/22210.232.28.1 to 210.232.31.254210.232.31.2551,022
9210.232.32.0/22210.232.32.1 to 210.232.35.254210.232.35.2551,022
10210.232.36.0/22210.232.36.1 to 210.232.39.254210.232.39.2551,022
11210.232.40.0/22210.232.40.1 to 210.232.43.254210.232.43.2551,022
12210.232.44.0/22210.232.44.1 to 210.232.47.254210.232.47.2551,022
13210.232.48.0/22210.232.48.1 to 210.232.51.254210.232.51.2551,022
14210.232.52.0/22210.232.52.1 to 210.232.55.254210.232.55.2551,022
15210.232.56.0/22210.232.56.1 to 210.232.59.254210.232.59.2551,022
16210.232.60.0/22210.232.60.1 to 210.232.63.254210.232.63.2551,022
17210.232.64.0/22210.232.64.1 to 210.232.67.254210.232.67.2551,022
18210.232.68.0/22210.232.68.1 to 210.232.71.254210.232.71.2551,022
19210.232.72.0/22210.232.72.1 to 210.232.75.254210.232.75.2551,022
20210.232.76.0/22210.232.76.1 to 210.232.79.254210.232.79.2551,022
21210.232.80.0/22210.232.80.1 to 210.232.83.254210.232.83.2551,022
22210.232.84.0/22210.232.84.1 to 210.232.87.254210.232.87.2551,022
23210.232.88.0/22210.232.88.1 to 210.232.91.254210.232.91.2551,022
24210.232.92.0/22210.232.92.1 to 210.232.95.254210.232.95.2551,022
25210.232.96.0/22210.232.96.1 to 210.232.99.254210.232.99.2551,022
26210.232.100.0/22210.232.100.1 to 210.232.103.254210.232.103.2551,022
27210.232.104.0/22210.232.104.1 to 210.232.107.254210.232.107.2551,022
28210.232.108.0/22210.232.108.1 to 210.232.111.254210.232.111.2551,022
29210.232.112.0/22210.232.112.1 to 210.232.115.254210.232.115.2551,022
30210.232.116.0/22210.232.116.1 to 210.232.119.254210.232.119.2551,022
31210.232.120.0/22210.232.120.1 to 210.232.123.254210.232.123.2551,022
32210.232.124.0/22210.232.124.1 to 210.232.127.254210.232.127.2551,022
33210.232.128.0/22210.232.128.1 to 210.232.131.254210.232.131.2551,022
34210.232.132.0/22210.232.132.1 to 210.232.135.254210.232.135.2551,022
35210.232.136.0/22210.232.136.1 to 210.232.139.254210.232.139.2551,022
36210.232.140.0/22210.232.140.1 to 210.232.143.254210.232.143.2551,022
37210.232.144.0/22210.232.144.1 to 210.232.147.254210.232.147.2551,022
38210.232.148.0/22210.232.148.1 to 210.232.151.254210.232.151.2551,022
39210.232.152.0/22210.232.152.1 to 210.232.155.254210.232.155.2551,022
40210.232.156.0/22210.232.156.1 to 210.232.159.254210.232.159.2551,022
41210.232.160.0/22210.232.160.1 to 210.232.163.254210.232.163.2551,022
42210.232.164.0/22210.232.164.1 to 210.232.167.254210.232.167.2551,022
43210.232.168.0/22210.232.168.1 to 210.232.171.254210.232.171.2551,022
44210.232.172.0/22210.232.172.1 to 210.232.175.254210.232.175.2551,022
45210.232.176.0/22210.232.176.1 to 210.232.179.254210.232.179.2551,022
46210.232.180.0/22210.232.180.1 to 210.232.183.254210.232.183.2551,022
47210.232.184.0/22210.232.184.1 to 210.232.187.254210.232.187.2551,022
48210.232.188.0/22210.232.188.1 to 210.232.191.254210.232.191.2551,022
49210.232.192.0/22210.232.192.1 to 210.232.195.254210.232.195.2551,022
50210.232.196.0/22210.232.196.1 to 210.232.199.254210.232.199.2551,022
51210.232.200.0/22210.232.200.1 to 210.232.203.254210.232.203.2551,022
52210.232.204.0/22210.232.204.1 to 210.232.207.254210.232.207.2551,022
53210.232.208.0/22210.232.208.1 to 210.232.211.254210.232.211.2551,022
54210.232.212.0/22210.232.212.1 to 210.232.215.254210.232.215.2551,022
55210.232.216.0/22210.232.216.1 to 210.232.219.254210.232.219.2551,022
56210.232.220.0/22210.232.220.1 to 210.232.223.254210.232.223.2551,022
57210.232.224.0/22210.232.224.1 to 210.232.227.254210.232.227.2551,022
58210.232.228.0/22210.232.228.1 to 210.232.231.254210.232.231.2551,022
59210.232.232.0/22210.232.232.1 to 210.232.235.254210.232.235.2551,022
60210.232.236.0/22210.232.236.1 to 210.232.239.254210.232.239.2551,022
61210.232.240.0/22210.232.240.1 to 210.232.243.254210.232.243.2551,022
62210.232.244.0/22210.232.244.1 to 210.232.247.254210.232.247.2551,022
63210.232.248.0/22210.232.248.1 to 210.232.251.254210.232.251.2551,022
64210.232.252.0/22210.232.252.1 to 210.232.255.254210.232.255.2551,022
65210.233.0.0/22210.233.0.1 to 210.233.3.254210.233.3.2551,022
66210.233.4.0/22210.233.4.1 to 210.233.7.254210.233.7.2551,022
67210.233.8.0/22210.233.8.1 to 210.233.11.254210.233.11.2551,022
68210.233.12.0/22210.233.12.1 to 210.233.15.254210.233.15.2551,022
69210.233.16.0/22210.233.16.1 to 210.233.19.254210.233.19.2551,022
70210.233.20.0/22210.233.20.1 to 210.233.23.254210.233.23.2551,022
71210.233.24.0/22210.233.24.1 to 210.233.27.254210.233.27.2551,022
72210.233.28.0/22210.233.28.1 to 210.233.31.254210.233.31.2551,022
73210.233.32.0/22210.233.32.1 to 210.233.35.254210.233.35.2551,022
74210.233.36.0/22210.233.36.1 to 210.233.39.254210.233.39.2551,022
75210.233.40.0/22210.233.40.1 to 210.233.43.254210.233.43.2551,022
76210.233.44.0/22210.233.44.1 to 210.233.47.254210.233.47.2551,022
77210.233.48.0/22210.233.48.1 to 210.233.51.254210.233.51.2551,022
78210.233.52.0/22210.233.52.1 to 210.233.55.254210.233.55.2551,022
79210.233.56.0/22210.233.56.1 to 210.233.59.254210.233.59.2551,022
80210.233.60.0/22210.233.60.1 to 210.233.63.254210.233.63.2551,022
81210.233.64.0/22210.233.64.1 to 210.233.67.254210.233.67.2551,022
82210.233.68.0/22210.233.68.1 to 210.233.71.254210.233.71.2551,022
83210.233.72.0/22210.233.72.1 to 210.233.75.254210.233.75.2551,022
84210.233.76.0/22210.233.76.1 to 210.233.79.254210.233.79.2551,022
85210.233.80.0/22210.233.80.1 to 210.233.83.254210.233.83.2551,022
86210.233.84.0/22210.233.84.1 to 210.233.87.254210.233.87.2551,022
87210.233.88.0/22210.233.88.1 to 210.233.91.254210.233.91.2551,022
88210.233.92.0/22210.233.92.1 to 210.233.95.254210.233.95.2551,022
89210.233.96.0/22210.233.96.1 to 210.233.99.254210.233.99.2551,022
90210.233.100.0/22210.233.100.1 to 210.233.103.254210.233.103.2551,022
91210.233.104.0/22210.233.104.1 to 210.233.107.254210.233.107.2551,022
92210.233.108.0/22210.233.108.1 to 210.233.111.254210.233.111.2551,022
93210.233.112.0/22210.233.112.1 to 210.233.115.254210.233.115.2551,022
94210.233.116.0/22210.233.116.1 to 210.233.119.254210.233.119.2551,022
95210.233.120.0/22210.233.120.1 to 210.233.123.254210.233.123.2551,022
96210.233.124.0/22210.233.124.1 to 210.233.127.254210.233.127.2551,022
97210.233.128.0/22210.233.128.1 to 210.233.131.254210.233.131.2551,022
98210.233.132.0/22210.233.132.1 to 210.233.135.254210.233.135.2551,022
99210.233.136.0/22210.233.136.1 to 210.233.139.254210.233.139.2551,022
100210.233.140.0/22210.233.140.1 to 210.233.143.254210.233.143.2551,022
101210.233.144.0/22210.233.144.1 to 210.233.147.254210.233.147.2551,022
102210.233.148.0/22210.233.148.1 to 210.233.151.254210.233.151.2551,022
103210.233.152.0/22210.233.152.1 to 210.233.155.254210.233.155.2551,022
104210.233.156.0/22210.233.156.1 to 210.233.159.254210.233.159.2551,022
105210.233.160.0/22210.233.160.1 to 210.233.163.254210.233.163.2551,022
106210.233.164.0/22210.233.164.1 to 210.233.167.254210.233.167.2551,022
107210.233.168.0/22210.233.168.1 to 210.233.171.254210.233.171.2551,022
108210.233.172.0/22210.233.172.1 to 210.233.175.254210.233.175.2551,022
109210.233.176.0/22210.233.176.1 to 210.233.179.254210.233.179.2551,022
110210.233.180.0/22210.233.180.1 to 210.233.183.254210.233.183.2551,022
111210.233.184.0/22210.233.184.1 to 210.233.187.254210.233.187.2551,022
112210.233.188.0/22210.233.188.1 to 210.233.191.254210.233.191.2551,022
113210.233.192.0/22210.233.192.1 to 210.233.195.254210.233.195.2551,022
114210.233.196.0/22210.233.196.1 to 210.233.199.254210.233.199.2551,022
115210.233.200.0/22210.233.200.1 to 210.233.203.254210.233.203.2551,022
116210.233.204.0/22210.233.204.1 to 210.233.207.254210.233.207.2551,022
117210.233.208.0/22210.233.208.1 to 210.233.211.254210.233.211.2551,022
118210.233.212.0/22210.233.212.1 to 210.233.215.254210.233.215.2551,022
119210.233.216.0/22210.233.216.1 to 210.233.219.254210.233.219.2551,022
120210.233.220.0/22210.233.220.1 to 210.233.223.254210.233.223.2551,022
121210.233.224.0/22210.233.224.1 to 210.233.227.254210.233.227.2551,022
122210.233.228.0/22210.233.228.1 to 210.233.231.254210.233.231.2551,022
123210.233.232.0/22210.233.232.1 to 210.233.235.254210.233.235.2551,022
124210.233.236.0/22210.233.236.1 to 210.233.239.254210.233.239.2551,022
125210.233.240.0/22210.233.240.1 to 210.233.243.254210.233.243.2551,022
126210.233.244.0/22210.233.244.1 to 210.233.247.254210.233.247.2551,022
127210.233.248.0/22210.233.248.1 to 210.233.251.254210.233.251.2551,022
128210.233.252.0/22210.233.252.1 to 210.233.255.254210.233.255.2551,022
129210.234.0.0/22210.234.0.1 to 210.234.3.254210.234.3.2551,022
130210.234.4.0/22210.234.4.1 to 210.234.7.254210.234.7.2551,022
131210.234.8.0/22210.234.8.1 to 210.234.11.254210.234.11.2551,022
132210.234.12.0/22210.234.12.1 to 210.234.15.254210.234.15.2551,022
133210.234.16.0/22210.234.16.1 to 210.234.19.254210.234.19.2551,022
134210.234.20.0/22210.234.20.1 to 210.234.23.254210.234.23.2551,022
135210.234.24.0/22210.234.24.1 to 210.234.27.254210.234.27.2551,022
136210.234.28.0/22210.234.28.1 to 210.234.31.254210.234.31.2551,022
137210.234.32.0/22210.234.32.1 to 210.234.35.254210.234.35.2551,022
138210.234.36.0/22210.234.36.1 to 210.234.39.254210.234.39.2551,022
139210.234.40.0/22210.234.40.1 to 210.234.43.254210.234.43.2551,022
140210.234.44.0/22210.234.44.1 to 210.234.47.254210.234.47.2551,022
141210.234.48.0/22210.234.48.1 to 210.234.51.254210.234.51.2551,022
142210.234.52.0/22210.234.52.1 to 210.234.55.254210.234.55.2551,022
143210.234.56.0/22210.234.56.1 to 210.234.59.254210.234.59.2551,022
144210.234.60.0/22210.234.60.1 to 210.234.63.254210.234.63.2551,022
145210.234.64.0/22210.234.64.1 to 210.234.67.254210.234.67.2551,022
146210.234.68.0/22210.234.68.1 to 210.234.71.254210.234.71.2551,022
147210.234.72.0/22210.234.72.1 to 210.234.75.254210.234.75.2551,022
148210.234.76.0/22210.234.76.1 to 210.234.79.254210.234.79.2551,022
149210.234.80.0/22210.234.80.1 to 210.234.83.254210.234.83.2551,022
150210.234.84.0/22210.234.84.1 to 210.234.87.254210.234.87.2551,022
151210.234.88.0/22210.234.88.1 to 210.234.91.254210.234.91.2551,022
152210.234.92.0/22210.234.92.1 to 210.234.95.254210.234.95.2551,022
153210.234.96.0/22210.234.96.1 to 210.234.99.254210.234.99.2551,022
154210.234.100.0/22210.234.100.1 to 210.234.103.254210.234.103.2551,022
155210.234.104.0/22210.234.104.1 to 210.234.107.254210.234.107.2551,022
156210.234.108.0/22210.234.108.1 to 210.234.111.254210.234.111.2551,022
157210.234.112.0/22210.234.112.1 to 210.234.115.254210.234.115.2551,022
158210.234.116.0/22210.234.116.1 to 210.234.119.254210.234.119.2551,022
159210.234.120.0/22210.234.120.1 to 210.234.123.254210.234.123.2551,022
160210.234.124.0/22210.234.124.1 to 210.234.127.254210.234.127.2551,022
161210.234.128.0/22210.234.128.1 to 210.234.131.254210.234.131.2551,022
162210.234.132.0/22210.234.132.1 to 210.234.135.254210.234.135.2551,022
163210.234.136.0/22210.234.136.1 to 210.234.139.254210.234.139.2551,022
164210.234.140.0/22210.234.140.1 to 210.234.143.254210.234.143.2551,022
165210.234.144.0/22210.234.144.1 to 210.234.147.254210.234.147.2551,022
166210.234.148.0/22210.234.148.1 to 210.234.151.254210.234.151.2551,022
167210.234.152.0/22210.234.152.1 to 210.234.155.254210.234.155.2551,022
168210.234.156.0/22210.234.156.1 to 210.234.159.254210.234.159.2551,022
169210.234.160.0/22210.234.160.1 to 210.234.163.254210.234.163.2551,022
170210.234.164.0/22210.234.164.1 to 210.234.167.254210.234.167.2551,022
171210.234.168.0/22210.234.168.1 to 210.234.171.254210.234.171.2551,022
172210.234.172.0/22210.234.172.1 to 210.234.175.254210.234.175.2551,022
173210.234.176.0/22210.234.176.1 to 210.234.179.254210.234.179.2551,022
174210.234.180.0/22210.234.180.1 to 210.234.183.254210.234.183.2551,022
175210.234.184.0/22210.234.184.1 to 210.234.187.254210.234.187.2551,022
176210.234.188.0/22210.234.188.1 to 210.234.191.254210.234.191.2551,022
177210.234.192.0/22210.234.192.1 to 210.234.195.254210.234.195.2551,022
178210.234.196.0/22210.234.196.1 to 210.234.199.254210.234.199.2551,022
179210.234.200.0/22210.234.200.1 to 210.234.203.254210.234.203.2551,022
180210.234.204.0/22210.234.204.1 to 210.234.207.254210.234.207.2551,022
181210.234.208.0/22210.234.208.1 to 210.234.211.254210.234.211.2551,022
182210.234.212.0/22210.234.212.1 to 210.234.215.254210.234.215.2551,022
183210.234.216.0/22210.234.216.1 to 210.234.219.254210.234.219.2551,022
184210.234.220.0/22210.234.220.1 to 210.234.223.254210.234.223.2551,022
185210.234.224.0/22210.234.224.1 to 210.234.227.254210.234.227.2551,022
186210.234.228.0/22210.234.228.1 to 210.234.231.254210.234.231.2551,022
187210.234.232.0/22210.234.232.1 to 210.234.235.254210.234.235.2551,022
188210.234.236.0/22210.234.236.1 to 210.234.239.254210.234.239.2551,022
189210.234.240.0/22210.234.240.1 to 210.234.243.254210.234.243.2551,022
190210.234.244.0/22210.234.244.1 to 210.234.247.254210.234.247.2551,022
191210.234.248.0/22210.234.248.1 to 210.234.251.254210.234.251.2551,022
192210.234.252.0/22210.234.252.1 to 210.234.255.254210.234.255.2551,022
193210.235.0.0/22210.235.0.1 to 210.235.3.254210.235.3.2551,022
194210.235.4.0/22210.235.4.1 to 210.235.7.254210.235.7.2551,022
195210.235.8.0/22210.235.8.1 to 210.235.11.254210.235.11.2551,022
196210.235.12.0/22210.235.12.1 to 210.235.15.254210.235.15.2551,022
197210.235.16.0/22210.235.16.1 to 210.235.19.254210.235.19.2551,022
198210.235.20.0/22210.235.20.1 to 210.235.23.254210.235.23.2551,022
199210.235.24.0/22210.235.24.1 to 210.235.27.254210.235.27.2551,022
200210.235.28.0/22210.235.28.1 to 210.235.31.254210.235.31.2551,022
201210.235.32.0/22210.235.32.1 to 210.235.35.254210.235.35.2551,022
202210.235.36.0/22210.235.36.1 to 210.235.39.254210.235.39.2551,022
203210.235.40.0/22210.235.40.1 to 210.235.43.254210.235.43.2551,022
204210.235.44.0/22210.235.44.1 to 210.235.47.254210.235.47.2551,022
205210.235.48.0/22210.235.48.1 to 210.235.51.254210.235.51.2551,022
206210.235.52.0/22210.235.52.1 to 210.235.55.254210.235.55.2551,022
207210.235.56.0/22210.235.56.1 to 210.235.59.254210.235.59.2551,022
208210.235.60.0/22210.235.60.1 to 210.235.63.254210.235.63.2551,022
209210.235.64.0/22210.235.64.1 to 210.235.67.254210.235.67.2551,022
210210.235.68.0/22210.235.68.1 to 210.235.71.254210.235.71.2551,022
211210.235.72.0/22210.235.72.1 to 210.235.75.254210.235.75.2551,022
212210.235.76.0/22210.235.76.1 to 210.235.79.254210.235.79.2551,022
213210.235.80.0/22210.235.80.1 to 210.235.83.254210.235.83.2551,022
214210.235.84.0/22210.235.84.1 to 210.235.87.254210.235.87.2551,022
215210.235.88.0/22210.235.88.1 to 210.235.91.254210.235.91.2551,022
216210.235.92.0/22210.235.92.1 to 210.235.95.254210.235.95.2551,022
217210.235.96.0/22210.235.96.1 to 210.235.99.254210.235.99.2551,022
218210.235.100.0/22210.235.100.1 to 210.235.103.254210.235.103.2551,022
219210.235.104.0/22210.235.104.1 to 210.235.107.254210.235.107.2551,022
220210.235.108.0/22210.235.108.1 to 210.235.111.254210.235.111.2551,022
221210.235.112.0/22210.235.112.1 to 210.235.115.254210.235.115.2551,022
222210.235.116.0/22210.235.116.1 to 210.235.119.254210.235.119.2551,022
223210.235.120.0/22210.235.120.1 to 210.235.123.254210.235.123.2551,022
224210.235.124.0/22210.235.124.1 to 210.235.127.254210.235.127.2551,022
225210.235.128.0/22210.235.128.1 to 210.235.131.254210.235.131.2551,022
226210.235.132.0/22210.235.132.1 to 210.235.135.254210.235.135.2551,022
227210.235.136.0/22210.235.136.1 to 210.235.139.254210.235.139.2551,022
228210.235.140.0/22210.235.140.1 to 210.235.143.254210.235.143.2551,022
229210.235.144.0/22210.235.144.1 to 210.235.147.254210.235.147.2551,022
230210.235.148.0/22210.235.148.1 to 210.235.151.254210.235.151.2551,022
231210.235.152.0/22210.235.152.1 to 210.235.155.254210.235.155.2551,022
232210.235.156.0/22210.235.156.1 to 210.235.159.254210.235.159.2551,022
233210.235.160.0/22210.235.160.1 to 210.235.163.254210.235.163.2551,022
234210.235.164.0/22210.235.164.1 to 210.235.167.254210.235.167.2551,022
235210.235.168.0/22210.235.168.1 to 210.235.171.254210.235.171.2551,022
236210.235.172.0/22210.235.172.1 to 210.235.175.254210.235.175.2551,022
237210.235.176.0/22210.235.176.1 to 210.235.179.254210.235.179.2551,022
238210.235.180.0/22210.235.180.1 to 210.235.183.254210.235.183.2551,022
239210.235.184.0/22210.235.184.1 to 210.235.187.254210.235.187.2551,022
240210.235.188.0/22210.235.188.1 to 210.235.191.254210.235.191.2551,022
241210.235.192.0/22210.235.192.1 to 210.235.195.254210.235.195.2551,022
242210.235.196.0/22210.235.196.1 to 210.235.199.254210.235.199.2551,022
243210.235.200.0/22210.235.200.1 to 210.235.203.254210.235.203.2551,022
244210.235.204.0/22210.235.204.1 to 210.235.207.254210.235.207.2551,022
245210.235.208.0/22210.235.208.1 to 210.235.211.254210.235.211.2551,022
246210.235.212.0/22210.235.212.1 to 210.235.215.254210.235.215.2551,022
247210.235.216.0/22210.235.216.1 to 210.235.219.254210.235.219.2551,022
248210.235.220.0/22210.235.220.1 to 210.235.223.254210.235.223.2551,022
249210.235.224.0/22210.235.224.1 to 210.235.227.254210.235.227.2551,022
250210.235.228.0/22210.235.228.1 to 210.235.231.254210.235.231.2551,022
251210.235.232.0/22210.235.232.1 to 210.235.235.254210.235.235.2551,022
252210.235.236.0/22210.235.236.1 to 210.235.239.254210.235.239.2551,022
253210.235.240.0/22210.235.240.1 to 210.235.243.254210.235.243.2551,022
254210.235.244.0/22210.235.244.1 to 210.235.247.254210.235.247.2551,022
255210.235.248.0/22210.235.248.1 to 210.235.251.254210.235.251.2551,022
256210.235.252.0/22210.235.252.1 to 210.235.255.254210.235.255.2551,022

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.