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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.

Network211.4.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
211.4.0.0
Broadcast address
211.7.255.255
First usable
211.4.0.1
Last usable
211.7.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
C (default /24)
As numbers
Hex D3040000 · Integer 3540254720 to 3540516863
Reverse DNS zones
4.211.in-addr.arpa
5.211.in-addr.arpa
6.211.in-addr.arpa
7.211.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11010011.00000100.00000000.00000000211.4.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11010011.00000100.00000000.00000000211.4.0.0
Broadcast11010011.00000111.11111111.11111111211.7.255.255
Split into smaller subnets/22
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

211.4.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1211.4.0.0/22211.4.0.1 to 211.4.3.254211.4.3.2551,022
2211.4.4.0/22211.4.4.1 to 211.4.7.254211.4.7.2551,022
3211.4.8.0/22211.4.8.1 to 211.4.11.254211.4.11.2551,022
4211.4.12.0/22211.4.12.1 to 211.4.15.254211.4.15.2551,022
5211.4.16.0/22211.4.16.1 to 211.4.19.254211.4.19.2551,022
6211.4.20.0/22211.4.20.1 to 211.4.23.254211.4.23.2551,022
7211.4.24.0/22211.4.24.1 to 211.4.27.254211.4.27.2551,022
8211.4.28.0/22211.4.28.1 to 211.4.31.254211.4.31.2551,022
9211.4.32.0/22211.4.32.1 to 211.4.35.254211.4.35.2551,022
10211.4.36.0/22211.4.36.1 to 211.4.39.254211.4.39.2551,022
11211.4.40.0/22211.4.40.1 to 211.4.43.254211.4.43.2551,022
12211.4.44.0/22211.4.44.1 to 211.4.47.254211.4.47.2551,022
13211.4.48.0/22211.4.48.1 to 211.4.51.254211.4.51.2551,022
14211.4.52.0/22211.4.52.1 to 211.4.55.254211.4.55.2551,022
15211.4.56.0/22211.4.56.1 to 211.4.59.254211.4.59.2551,022
16211.4.60.0/22211.4.60.1 to 211.4.63.254211.4.63.2551,022
17211.4.64.0/22211.4.64.1 to 211.4.67.254211.4.67.2551,022
18211.4.68.0/22211.4.68.1 to 211.4.71.254211.4.71.2551,022
19211.4.72.0/22211.4.72.1 to 211.4.75.254211.4.75.2551,022
20211.4.76.0/22211.4.76.1 to 211.4.79.254211.4.79.2551,022
21211.4.80.0/22211.4.80.1 to 211.4.83.254211.4.83.2551,022
22211.4.84.0/22211.4.84.1 to 211.4.87.254211.4.87.2551,022
23211.4.88.0/22211.4.88.1 to 211.4.91.254211.4.91.2551,022
24211.4.92.0/22211.4.92.1 to 211.4.95.254211.4.95.2551,022
25211.4.96.0/22211.4.96.1 to 211.4.99.254211.4.99.2551,022
26211.4.100.0/22211.4.100.1 to 211.4.103.254211.4.103.2551,022
27211.4.104.0/22211.4.104.1 to 211.4.107.254211.4.107.2551,022
28211.4.108.0/22211.4.108.1 to 211.4.111.254211.4.111.2551,022
29211.4.112.0/22211.4.112.1 to 211.4.115.254211.4.115.2551,022
30211.4.116.0/22211.4.116.1 to 211.4.119.254211.4.119.2551,022
31211.4.120.0/22211.4.120.1 to 211.4.123.254211.4.123.2551,022
32211.4.124.0/22211.4.124.1 to 211.4.127.254211.4.127.2551,022
33211.4.128.0/22211.4.128.1 to 211.4.131.254211.4.131.2551,022
34211.4.132.0/22211.4.132.1 to 211.4.135.254211.4.135.2551,022
35211.4.136.0/22211.4.136.1 to 211.4.139.254211.4.139.2551,022
36211.4.140.0/22211.4.140.1 to 211.4.143.254211.4.143.2551,022
37211.4.144.0/22211.4.144.1 to 211.4.147.254211.4.147.2551,022
38211.4.148.0/22211.4.148.1 to 211.4.151.254211.4.151.2551,022
39211.4.152.0/22211.4.152.1 to 211.4.155.254211.4.155.2551,022
40211.4.156.0/22211.4.156.1 to 211.4.159.254211.4.159.2551,022
41211.4.160.0/22211.4.160.1 to 211.4.163.254211.4.163.2551,022
42211.4.164.0/22211.4.164.1 to 211.4.167.254211.4.167.2551,022
43211.4.168.0/22211.4.168.1 to 211.4.171.254211.4.171.2551,022
44211.4.172.0/22211.4.172.1 to 211.4.175.254211.4.175.2551,022
45211.4.176.0/22211.4.176.1 to 211.4.179.254211.4.179.2551,022
46211.4.180.0/22211.4.180.1 to 211.4.183.254211.4.183.2551,022
47211.4.184.0/22211.4.184.1 to 211.4.187.254211.4.187.2551,022
48211.4.188.0/22211.4.188.1 to 211.4.191.254211.4.191.2551,022
49211.4.192.0/22211.4.192.1 to 211.4.195.254211.4.195.2551,022
50211.4.196.0/22211.4.196.1 to 211.4.199.254211.4.199.2551,022
51211.4.200.0/22211.4.200.1 to 211.4.203.254211.4.203.2551,022
52211.4.204.0/22211.4.204.1 to 211.4.207.254211.4.207.2551,022
53211.4.208.0/22211.4.208.1 to 211.4.211.254211.4.211.2551,022
54211.4.212.0/22211.4.212.1 to 211.4.215.254211.4.215.2551,022
55211.4.216.0/22211.4.216.1 to 211.4.219.254211.4.219.2551,022
56211.4.220.0/22211.4.220.1 to 211.4.223.254211.4.223.2551,022
57211.4.224.0/22211.4.224.1 to 211.4.227.254211.4.227.2551,022
58211.4.228.0/22211.4.228.1 to 211.4.231.254211.4.231.2551,022
59211.4.232.0/22211.4.232.1 to 211.4.235.254211.4.235.2551,022
60211.4.236.0/22211.4.236.1 to 211.4.239.254211.4.239.2551,022
61211.4.240.0/22211.4.240.1 to 211.4.243.254211.4.243.2551,022
62211.4.244.0/22211.4.244.1 to 211.4.247.254211.4.247.2551,022
63211.4.248.0/22211.4.248.1 to 211.4.251.254211.4.251.2551,022
64211.4.252.0/22211.4.252.1 to 211.4.255.254211.4.255.2551,022
65211.5.0.0/22211.5.0.1 to 211.5.3.254211.5.3.2551,022
66211.5.4.0/22211.5.4.1 to 211.5.7.254211.5.7.2551,022
67211.5.8.0/22211.5.8.1 to 211.5.11.254211.5.11.2551,022
68211.5.12.0/22211.5.12.1 to 211.5.15.254211.5.15.2551,022
69211.5.16.0/22211.5.16.1 to 211.5.19.254211.5.19.2551,022
70211.5.20.0/22211.5.20.1 to 211.5.23.254211.5.23.2551,022
71211.5.24.0/22211.5.24.1 to 211.5.27.254211.5.27.2551,022
72211.5.28.0/22211.5.28.1 to 211.5.31.254211.5.31.2551,022
73211.5.32.0/22211.5.32.1 to 211.5.35.254211.5.35.2551,022
74211.5.36.0/22211.5.36.1 to 211.5.39.254211.5.39.2551,022
75211.5.40.0/22211.5.40.1 to 211.5.43.254211.5.43.2551,022
76211.5.44.0/22211.5.44.1 to 211.5.47.254211.5.47.2551,022
77211.5.48.0/22211.5.48.1 to 211.5.51.254211.5.51.2551,022
78211.5.52.0/22211.5.52.1 to 211.5.55.254211.5.55.2551,022
79211.5.56.0/22211.5.56.1 to 211.5.59.254211.5.59.2551,022
80211.5.60.0/22211.5.60.1 to 211.5.63.254211.5.63.2551,022
81211.5.64.0/22211.5.64.1 to 211.5.67.254211.5.67.2551,022
82211.5.68.0/22211.5.68.1 to 211.5.71.254211.5.71.2551,022
83211.5.72.0/22211.5.72.1 to 211.5.75.254211.5.75.2551,022
84211.5.76.0/22211.5.76.1 to 211.5.79.254211.5.79.2551,022
85211.5.80.0/22211.5.80.1 to 211.5.83.254211.5.83.2551,022
86211.5.84.0/22211.5.84.1 to 211.5.87.254211.5.87.2551,022
87211.5.88.0/22211.5.88.1 to 211.5.91.254211.5.91.2551,022
88211.5.92.0/22211.5.92.1 to 211.5.95.254211.5.95.2551,022
89211.5.96.0/22211.5.96.1 to 211.5.99.254211.5.99.2551,022
90211.5.100.0/22211.5.100.1 to 211.5.103.254211.5.103.2551,022
91211.5.104.0/22211.5.104.1 to 211.5.107.254211.5.107.2551,022
92211.5.108.0/22211.5.108.1 to 211.5.111.254211.5.111.2551,022
93211.5.112.0/22211.5.112.1 to 211.5.115.254211.5.115.2551,022
94211.5.116.0/22211.5.116.1 to 211.5.119.254211.5.119.2551,022
95211.5.120.0/22211.5.120.1 to 211.5.123.254211.5.123.2551,022
96211.5.124.0/22211.5.124.1 to 211.5.127.254211.5.127.2551,022
97211.5.128.0/22211.5.128.1 to 211.5.131.254211.5.131.2551,022
98211.5.132.0/22211.5.132.1 to 211.5.135.254211.5.135.2551,022
99211.5.136.0/22211.5.136.1 to 211.5.139.254211.5.139.2551,022
100211.5.140.0/22211.5.140.1 to 211.5.143.254211.5.143.2551,022
101211.5.144.0/22211.5.144.1 to 211.5.147.254211.5.147.2551,022
102211.5.148.0/22211.5.148.1 to 211.5.151.254211.5.151.2551,022
103211.5.152.0/22211.5.152.1 to 211.5.155.254211.5.155.2551,022
104211.5.156.0/22211.5.156.1 to 211.5.159.254211.5.159.2551,022
105211.5.160.0/22211.5.160.1 to 211.5.163.254211.5.163.2551,022
106211.5.164.0/22211.5.164.1 to 211.5.167.254211.5.167.2551,022
107211.5.168.0/22211.5.168.1 to 211.5.171.254211.5.171.2551,022
108211.5.172.0/22211.5.172.1 to 211.5.175.254211.5.175.2551,022
109211.5.176.0/22211.5.176.1 to 211.5.179.254211.5.179.2551,022
110211.5.180.0/22211.5.180.1 to 211.5.183.254211.5.183.2551,022
111211.5.184.0/22211.5.184.1 to 211.5.187.254211.5.187.2551,022
112211.5.188.0/22211.5.188.1 to 211.5.191.254211.5.191.2551,022
113211.5.192.0/22211.5.192.1 to 211.5.195.254211.5.195.2551,022
114211.5.196.0/22211.5.196.1 to 211.5.199.254211.5.199.2551,022
115211.5.200.0/22211.5.200.1 to 211.5.203.254211.5.203.2551,022
116211.5.204.0/22211.5.204.1 to 211.5.207.254211.5.207.2551,022
117211.5.208.0/22211.5.208.1 to 211.5.211.254211.5.211.2551,022
118211.5.212.0/22211.5.212.1 to 211.5.215.254211.5.215.2551,022
119211.5.216.0/22211.5.216.1 to 211.5.219.254211.5.219.2551,022
120211.5.220.0/22211.5.220.1 to 211.5.223.254211.5.223.2551,022
121211.5.224.0/22211.5.224.1 to 211.5.227.254211.5.227.2551,022
122211.5.228.0/22211.5.228.1 to 211.5.231.254211.5.231.2551,022
123211.5.232.0/22211.5.232.1 to 211.5.235.254211.5.235.2551,022
124211.5.236.0/22211.5.236.1 to 211.5.239.254211.5.239.2551,022
125211.5.240.0/22211.5.240.1 to 211.5.243.254211.5.243.2551,022
126211.5.244.0/22211.5.244.1 to 211.5.247.254211.5.247.2551,022
127211.5.248.0/22211.5.248.1 to 211.5.251.254211.5.251.2551,022
128211.5.252.0/22211.5.252.1 to 211.5.255.254211.5.255.2551,022
129211.6.0.0/22211.6.0.1 to 211.6.3.254211.6.3.2551,022
130211.6.4.0/22211.6.4.1 to 211.6.7.254211.6.7.2551,022
131211.6.8.0/22211.6.8.1 to 211.6.11.254211.6.11.2551,022
132211.6.12.0/22211.6.12.1 to 211.6.15.254211.6.15.2551,022
133211.6.16.0/22211.6.16.1 to 211.6.19.254211.6.19.2551,022
134211.6.20.0/22211.6.20.1 to 211.6.23.254211.6.23.2551,022
135211.6.24.0/22211.6.24.1 to 211.6.27.254211.6.27.2551,022
136211.6.28.0/22211.6.28.1 to 211.6.31.254211.6.31.2551,022
137211.6.32.0/22211.6.32.1 to 211.6.35.254211.6.35.2551,022
138211.6.36.0/22211.6.36.1 to 211.6.39.254211.6.39.2551,022
139211.6.40.0/22211.6.40.1 to 211.6.43.254211.6.43.2551,022
140211.6.44.0/22211.6.44.1 to 211.6.47.254211.6.47.2551,022
141211.6.48.0/22211.6.48.1 to 211.6.51.254211.6.51.2551,022
142211.6.52.0/22211.6.52.1 to 211.6.55.254211.6.55.2551,022
143211.6.56.0/22211.6.56.1 to 211.6.59.254211.6.59.2551,022
144211.6.60.0/22211.6.60.1 to 211.6.63.254211.6.63.2551,022
145211.6.64.0/22211.6.64.1 to 211.6.67.254211.6.67.2551,022
146211.6.68.0/22211.6.68.1 to 211.6.71.254211.6.71.2551,022
147211.6.72.0/22211.6.72.1 to 211.6.75.254211.6.75.2551,022
148211.6.76.0/22211.6.76.1 to 211.6.79.254211.6.79.2551,022
149211.6.80.0/22211.6.80.1 to 211.6.83.254211.6.83.2551,022
150211.6.84.0/22211.6.84.1 to 211.6.87.254211.6.87.2551,022
151211.6.88.0/22211.6.88.1 to 211.6.91.254211.6.91.2551,022
152211.6.92.0/22211.6.92.1 to 211.6.95.254211.6.95.2551,022
153211.6.96.0/22211.6.96.1 to 211.6.99.254211.6.99.2551,022
154211.6.100.0/22211.6.100.1 to 211.6.103.254211.6.103.2551,022
155211.6.104.0/22211.6.104.1 to 211.6.107.254211.6.107.2551,022
156211.6.108.0/22211.6.108.1 to 211.6.111.254211.6.111.2551,022
157211.6.112.0/22211.6.112.1 to 211.6.115.254211.6.115.2551,022
158211.6.116.0/22211.6.116.1 to 211.6.119.254211.6.119.2551,022
159211.6.120.0/22211.6.120.1 to 211.6.123.254211.6.123.2551,022
160211.6.124.0/22211.6.124.1 to 211.6.127.254211.6.127.2551,022
161211.6.128.0/22211.6.128.1 to 211.6.131.254211.6.131.2551,022
162211.6.132.0/22211.6.132.1 to 211.6.135.254211.6.135.2551,022
163211.6.136.0/22211.6.136.1 to 211.6.139.254211.6.139.2551,022
164211.6.140.0/22211.6.140.1 to 211.6.143.254211.6.143.2551,022
165211.6.144.0/22211.6.144.1 to 211.6.147.254211.6.147.2551,022
166211.6.148.0/22211.6.148.1 to 211.6.151.254211.6.151.2551,022
167211.6.152.0/22211.6.152.1 to 211.6.155.254211.6.155.2551,022
168211.6.156.0/22211.6.156.1 to 211.6.159.254211.6.159.2551,022
169211.6.160.0/22211.6.160.1 to 211.6.163.254211.6.163.2551,022
170211.6.164.0/22211.6.164.1 to 211.6.167.254211.6.167.2551,022
171211.6.168.0/22211.6.168.1 to 211.6.171.254211.6.171.2551,022
172211.6.172.0/22211.6.172.1 to 211.6.175.254211.6.175.2551,022
173211.6.176.0/22211.6.176.1 to 211.6.179.254211.6.179.2551,022
174211.6.180.0/22211.6.180.1 to 211.6.183.254211.6.183.2551,022
175211.6.184.0/22211.6.184.1 to 211.6.187.254211.6.187.2551,022
176211.6.188.0/22211.6.188.1 to 211.6.191.254211.6.191.2551,022
177211.6.192.0/22211.6.192.1 to 211.6.195.254211.6.195.2551,022
178211.6.196.0/22211.6.196.1 to 211.6.199.254211.6.199.2551,022
179211.6.200.0/22211.6.200.1 to 211.6.203.254211.6.203.2551,022
180211.6.204.0/22211.6.204.1 to 211.6.207.254211.6.207.2551,022
181211.6.208.0/22211.6.208.1 to 211.6.211.254211.6.211.2551,022
182211.6.212.0/22211.6.212.1 to 211.6.215.254211.6.215.2551,022
183211.6.216.0/22211.6.216.1 to 211.6.219.254211.6.219.2551,022
184211.6.220.0/22211.6.220.1 to 211.6.223.254211.6.223.2551,022
185211.6.224.0/22211.6.224.1 to 211.6.227.254211.6.227.2551,022
186211.6.228.0/22211.6.228.1 to 211.6.231.254211.6.231.2551,022
187211.6.232.0/22211.6.232.1 to 211.6.235.254211.6.235.2551,022
188211.6.236.0/22211.6.236.1 to 211.6.239.254211.6.239.2551,022
189211.6.240.0/22211.6.240.1 to 211.6.243.254211.6.243.2551,022
190211.6.244.0/22211.6.244.1 to 211.6.247.254211.6.247.2551,022
191211.6.248.0/22211.6.248.1 to 211.6.251.254211.6.251.2551,022
192211.6.252.0/22211.6.252.1 to 211.6.255.254211.6.255.2551,022
193211.7.0.0/22211.7.0.1 to 211.7.3.254211.7.3.2551,022
194211.7.4.0/22211.7.4.1 to 211.7.7.254211.7.7.2551,022
195211.7.8.0/22211.7.8.1 to 211.7.11.254211.7.11.2551,022
196211.7.12.0/22211.7.12.1 to 211.7.15.254211.7.15.2551,022
197211.7.16.0/22211.7.16.1 to 211.7.19.254211.7.19.2551,022
198211.7.20.0/22211.7.20.1 to 211.7.23.254211.7.23.2551,022
199211.7.24.0/22211.7.24.1 to 211.7.27.254211.7.27.2551,022
200211.7.28.0/22211.7.28.1 to 211.7.31.254211.7.31.2551,022
201211.7.32.0/22211.7.32.1 to 211.7.35.254211.7.35.2551,022
202211.7.36.0/22211.7.36.1 to 211.7.39.254211.7.39.2551,022
203211.7.40.0/22211.7.40.1 to 211.7.43.254211.7.43.2551,022
204211.7.44.0/22211.7.44.1 to 211.7.47.254211.7.47.2551,022
205211.7.48.0/22211.7.48.1 to 211.7.51.254211.7.51.2551,022
206211.7.52.0/22211.7.52.1 to 211.7.55.254211.7.55.2551,022
207211.7.56.0/22211.7.56.1 to 211.7.59.254211.7.59.2551,022
208211.7.60.0/22211.7.60.1 to 211.7.63.254211.7.63.2551,022
209211.7.64.0/22211.7.64.1 to 211.7.67.254211.7.67.2551,022
210211.7.68.0/22211.7.68.1 to 211.7.71.254211.7.71.2551,022
211211.7.72.0/22211.7.72.1 to 211.7.75.254211.7.75.2551,022
212211.7.76.0/22211.7.76.1 to 211.7.79.254211.7.79.2551,022
213211.7.80.0/22211.7.80.1 to 211.7.83.254211.7.83.2551,022
214211.7.84.0/22211.7.84.1 to 211.7.87.254211.7.87.2551,022
215211.7.88.0/22211.7.88.1 to 211.7.91.254211.7.91.2551,022
216211.7.92.0/22211.7.92.1 to 211.7.95.254211.7.95.2551,022
217211.7.96.0/22211.7.96.1 to 211.7.99.254211.7.99.2551,022
218211.7.100.0/22211.7.100.1 to 211.7.103.254211.7.103.2551,022
219211.7.104.0/22211.7.104.1 to 211.7.107.254211.7.107.2551,022
220211.7.108.0/22211.7.108.1 to 211.7.111.254211.7.111.2551,022
221211.7.112.0/22211.7.112.1 to 211.7.115.254211.7.115.2551,022
222211.7.116.0/22211.7.116.1 to 211.7.119.254211.7.119.2551,022
223211.7.120.0/22211.7.120.1 to 211.7.123.254211.7.123.2551,022
224211.7.124.0/22211.7.124.1 to 211.7.127.254211.7.127.2551,022
225211.7.128.0/22211.7.128.1 to 211.7.131.254211.7.131.2551,022
226211.7.132.0/22211.7.132.1 to 211.7.135.254211.7.135.2551,022
227211.7.136.0/22211.7.136.1 to 211.7.139.254211.7.139.2551,022
228211.7.140.0/22211.7.140.1 to 211.7.143.254211.7.143.2551,022
229211.7.144.0/22211.7.144.1 to 211.7.147.254211.7.147.2551,022
230211.7.148.0/22211.7.148.1 to 211.7.151.254211.7.151.2551,022
231211.7.152.0/22211.7.152.1 to 211.7.155.254211.7.155.2551,022
232211.7.156.0/22211.7.156.1 to 211.7.159.254211.7.159.2551,022
233211.7.160.0/22211.7.160.1 to 211.7.163.254211.7.163.2551,022
234211.7.164.0/22211.7.164.1 to 211.7.167.254211.7.167.2551,022
235211.7.168.0/22211.7.168.1 to 211.7.171.254211.7.171.2551,022
236211.7.172.0/22211.7.172.1 to 211.7.175.254211.7.175.2551,022
237211.7.176.0/22211.7.176.1 to 211.7.179.254211.7.179.2551,022
238211.7.180.0/22211.7.180.1 to 211.7.183.254211.7.183.2551,022
239211.7.184.0/22211.7.184.1 to 211.7.187.254211.7.187.2551,022
240211.7.188.0/22211.7.188.1 to 211.7.191.254211.7.191.2551,022
241211.7.192.0/22211.7.192.1 to 211.7.195.254211.7.195.2551,022
242211.7.196.0/22211.7.196.1 to 211.7.199.254211.7.199.2551,022
243211.7.200.0/22211.7.200.1 to 211.7.203.254211.7.203.2551,022
244211.7.204.0/22211.7.204.1 to 211.7.207.254211.7.207.2551,022
245211.7.208.0/22211.7.208.1 to 211.7.211.254211.7.211.2551,022
246211.7.212.0/22211.7.212.1 to 211.7.215.254211.7.215.2551,022
247211.7.216.0/22211.7.216.1 to 211.7.219.254211.7.219.2551,022
248211.7.220.0/22211.7.220.1 to 211.7.223.254211.7.223.2551,022
249211.7.224.0/22211.7.224.1 to 211.7.227.254211.7.227.2551,022
250211.7.228.0/22211.7.228.1 to 211.7.231.254211.7.231.2551,022
251211.7.232.0/22211.7.232.1 to 211.7.235.254211.7.235.2551,022
252211.7.236.0/22211.7.236.1 to 211.7.239.254211.7.239.2551,022
253211.7.240.0/22211.7.240.1 to 211.7.243.254211.7.243.2551,022
254211.7.244.0/22211.7.244.1 to 211.7.247.254211.7.247.2551,022
255211.7.248.0/22211.7.248.1 to 211.7.251.254211.7.251.2551,022
256211.7.252.0/22211.7.252.1 to 211.7.255.254211.7.255.2551,022

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.