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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.

Network252.64.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
252.64.0.0
Broadcast address
252.95.255.255
First usable
252.64.0.1
Last usable
252.95.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Reserved 240.0.0.0/4
Future use; not usable on most systems
Old class
E (reserved)
As numbers
Hex FC400000 · Integer 4232052736 to 4234149887
Reverse DNS zones
64.252.in-addr.arpa
65.252.in-addr.arpa
66.252.in-addr.arpa
67.252.in-addr.arpa
68.252.in-addr.arpa
69.252.in-addr.arpa
70.252.in-addr.arpa
71.252.in-addr.arpa
72.252.in-addr.arpa
73.252.in-addr.arpa
74.252.in-addr.arpa
75.252.in-addr.arpa
76.252.in-addr.arpa
77.252.in-addr.arpa
78.252.in-addr.arpa
79.252.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11111100.01000000.00000000.00000000252.64.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11111100.01000000.00000000.00000000252.64.0.0
Broadcast11111100.01011111.11111111.11111111252.95.255.255
Split into smaller subnets/22
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

252.64.0.0/11 makes 2,048 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1252.64.0.0/22252.64.0.1 to 252.64.3.254252.64.3.2551,022
2252.64.4.0/22252.64.4.1 to 252.64.7.254252.64.7.2551,022
3252.64.8.0/22252.64.8.1 to 252.64.11.254252.64.11.2551,022
4252.64.12.0/22252.64.12.1 to 252.64.15.254252.64.15.2551,022
5252.64.16.0/22252.64.16.1 to 252.64.19.254252.64.19.2551,022
6252.64.20.0/22252.64.20.1 to 252.64.23.254252.64.23.2551,022
7252.64.24.0/22252.64.24.1 to 252.64.27.254252.64.27.2551,022
8252.64.28.0/22252.64.28.1 to 252.64.31.254252.64.31.2551,022
9252.64.32.0/22252.64.32.1 to 252.64.35.254252.64.35.2551,022
10252.64.36.0/22252.64.36.1 to 252.64.39.254252.64.39.2551,022
11252.64.40.0/22252.64.40.1 to 252.64.43.254252.64.43.2551,022
12252.64.44.0/22252.64.44.1 to 252.64.47.254252.64.47.2551,022
13252.64.48.0/22252.64.48.1 to 252.64.51.254252.64.51.2551,022
14252.64.52.0/22252.64.52.1 to 252.64.55.254252.64.55.2551,022
15252.64.56.0/22252.64.56.1 to 252.64.59.254252.64.59.2551,022
16252.64.60.0/22252.64.60.1 to 252.64.63.254252.64.63.2551,022
17252.64.64.0/22252.64.64.1 to 252.64.67.254252.64.67.2551,022
18252.64.68.0/22252.64.68.1 to 252.64.71.254252.64.71.2551,022
19252.64.72.0/22252.64.72.1 to 252.64.75.254252.64.75.2551,022
20252.64.76.0/22252.64.76.1 to 252.64.79.254252.64.79.2551,022
21252.64.80.0/22252.64.80.1 to 252.64.83.254252.64.83.2551,022
22252.64.84.0/22252.64.84.1 to 252.64.87.254252.64.87.2551,022
23252.64.88.0/22252.64.88.1 to 252.64.91.254252.64.91.2551,022
24252.64.92.0/22252.64.92.1 to 252.64.95.254252.64.95.2551,022
25252.64.96.0/22252.64.96.1 to 252.64.99.254252.64.99.2551,022
26252.64.100.0/22252.64.100.1 to 252.64.103.254252.64.103.2551,022
27252.64.104.0/22252.64.104.1 to 252.64.107.254252.64.107.2551,022
28252.64.108.0/22252.64.108.1 to 252.64.111.254252.64.111.2551,022
29252.64.112.0/22252.64.112.1 to 252.64.115.254252.64.115.2551,022
30252.64.116.0/22252.64.116.1 to 252.64.119.254252.64.119.2551,022
31252.64.120.0/22252.64.120.1 to 252.64.123.254252.64.123.2551,022
32252.64.124.0/22252.64.124.1 to 252.64.127.254252.64.127.2551,022
33252.64.128.0/22252.64.128.1 to 252.64.131.254252.64.131.2551,022
34252.64.132.0/22252.64.132.1 to 252.64.135.254252.64.135.2551,022
35252.64.136.0/22252.64.136.1 to 252.64.139.254252.64.139.2551,022
36252.64.140.0/22252.64.140.1 to 252.64.143.254252.64.143.2551,022
37252.64.144.0/22252.64.144.1 to 252.64.147.254252.64.147.2551,022
38252.64.148.0/22252.64.148.1 to 252.64.151.254252.64.151.2551,022
39252.64.152.0/22252.64.152.1 to 252.64.155.254252.64.155.2551,022
40252.64.156.0/22252.64.156.1 to 252.64.159.254252.64.159.2551,022
41252.64.160.0/22252.64.160.1 to 252.64.163.254252.64.163.2551,022
42252.64.164.0/22252.64.164.1 to 252.64.167.254252.64.167.2551,022
43252.64.168.0/22252.64.168.1 to 252.64.171.254252.64.171.2551,022
44252.64.172.0/22252.64.172.1 to 252.64.175.254252.64.175.2551,022
45252.64.176.0/22252.64.176.1 to 252.64.179.254252.64.179.2551,022
46252.64.180.0/22252.64.180.1 to 252.64.183.254252.64.183.2551,022
47252.64.184.0/22252.64.184.1 to 252.64.187.254252.64.187.2551,022
48252.64.188.0/22252.64.188.1 to 252.64.191.254252.64.191.2551,022
49252.64.192.0/22252.64.192.1 to 252.64.195.254252.64.195.2551,022
50252.64.196.0/22252.64.196.1 to 252.64.199.254252.64.199.2551,022
51252.64.200.0/22252.64.200.1 to 252.64.203.254252.64.203.2551,022
52252.64.204.0/22252.64.204.1 to 252.64.207.254252.64.207.2551,022
53252.64.208.0/22252.64.208.1 to 252.64.211.254252.64.211.2551,022
54252.64.212.0/22252.64.212.1 to 252.64.215.254252.64.215.2551,022
55252.64.216.0/22252.64.216.1 to 252.64.219.254252.64.219.2551,022
56252.64.220.0/22252.64.220.1 to 252.64.223.254252.64.223.2551,022
57252.64.224.0/22252.64.224.1 to 252.64.227.254252.64.227.2551,022
58252.64.228.0/22252.64.228.1 to 252.64.231.254252.64.231.2551,022
59252.64.232.0/22252.64.232.1 to 252.64.235.254252.64.235.2551,022
60252.64.236.0/22252.64.236.1 to 252.64.239.254252.64.239.2551,022
61252.64.240.0/22252.64.240.1 to 252.64.243.254252.64.243.2551,022
62252.64.244.0/22252.64.244.1 to 252.64.247.254252.64.247.2551,022
63252.64.248.0/22252.64.248.1 to 252.64.251.254252.64.251.2551,022
64252.64.252.0/22252.64.252.1 to 252.64.255.254252.64.255.2551,022
65252.65.0.0/22252.65.0.1 to 252.65.3.254252.65.3.2551,022
66252.65.4.0/22252.65.4.1 to 252.65.7.254252.65.7.2551,022
67252.65.8.0/22252.65.8.1 to 252.65.11.254252.65.11.2551,022
68252.65.12.0/22252.65.12.1 to 252.65.15.254252.65.15.2551,022
69252.65.16.0/22252.65.16.1 to 252.65.19.254252.65.19.2551,022
70252.65.20.0/22252.65.20.1 to 252.65.23.254252.65.23.2551,022
71252.65.24.0/22252.65.24.1 to 252.65.27.254252.65.27.2551,022
72252.65.28.0/22252.65.28.1 to 252.65.31.254252.65.31.2551,022
73252.65.32.0/22252.65.32.1 to 252.65.35.254252.65.35.2551,022
74252.65.36.0/22252.65.36.1 to 252.65.39.254252.65.39.2551,022
75252.65.40.0/22252.65.40.1 to 252.65.43.254252.65.43.2551,022
76252.65.44.0/22252.65.44.1 to 252.65.47.254252.65.47.2551,022
77252.65.48.0/22252.65.48.1 to 252.65.51.254252.65.51.2551,022
78252.65.52.0/22252.65.52.1 to 252.65.55.254252.65.55.2551,022
79252.65.56.0/22252.65.56.1 to 252.65.59.254252.65.59.2551,022
80252.65.60.0/22252.65.60.1 to 252.65.63.254252.65.63.2551,022
81252.65.64.0/22252.65.64.1 to 252.65.67.254252.65.67.2551,022
82252.65.68.0/22252.65.68.1 to 252.65.71.254252.65.71.2551,022
83252.65.72.0/22252.65.72.1 to 252.65.75.254252.65.75.2551,022
84252.65.76.0/22252.65.76.1 to 252.65.79.254252.65.79.2551,022
85252.65.80.0/22252.65.80.1 to 252.65.83.254252.65.83.2551,022
86252.65.84.0/22252.65.84.1 to 252.65.87.254252.65.87.2551,022
87252.65.88.0/22252.65.88.1 to 252.65.91.254252.65.91.2551,022
88252.65.92.0/22252.65.92.1 to 252.65.95.254252.65.95.2551,022
89252.65.96.0/22252.65.96.1 to 252.65.99.254252.65.99.2551,022
90252.65.100.0/22252.65.100.1 to 252.65.103.254252.65.103.2551,022
91252.65.104.0/22252.65.104.1 to 252.65.107.254252.65.107.2551,022
92252.65.108.0/22252.65.108.1 to 252.65.111.254252.65.111.2551,022
93252.65.112.0/22252.65.112.1 to 252.65.115.254252.65.115.2551,022
94252.65.116.0/22252.65.116.1 to 252.65.119.254252.65.119.2551,022
95252.65.120.0/22252.65.120.1 to 252.65.123.254252.65.123.2551,022
96252.65.124.0/22252.65.124.1 to 252.65.127.254252.65.127.2551,022
97252.65.128.0/22252.65.128.1 to 252.65.131.254252.65.131.2551,022
98252.65.132.0/22252.65.132.1 to 252.65.135.254252.65.135.2551,022
99252.65.136.0/22252.65.136.1 to 252.65.139.254252.65.139.2551,022
100252.65.140.0/22252.65.140.1 to 252.65.143.254252.65.143.2551,022
101252.65.144.0/22252.65.144.1 to 252.65.147.254252.65.147.2551,022
102252.65.148.0/22252.65.148.1 to 252.65.151.254252.65.151.2551,022
103252.65.152.0/22252.65.152.1 to 252.65.155.254252.65.155.2551,022
104252.65.156.0/22252.65.156.1 to 252.65.159.254252.65.159.2551,022
105252.65.160.0/22252.65.160.1 to 252.65.163.254252.65.163.2551,022
106252.65.164.0/22252.65.164.1 to 252.65.167.254252.65.167.2551,022
107252.65.168.0/22252.65.168.1 to 252.65.171.254252.65.171.2551,022
108252.65.172.0/22252.65.172.1 to 252.65.175.254252.65.175.2551,022
109252.65.176.0/22252.65.176.1 to 252.65.179.254252.65.179.2551,022
110252.65.180.0/22252.65.180.1 to 252.65.183.254252.65.183.2551,022
111252.65.184.0/22252.65.184.1 to 252.65.187.254252.65.187.2551,022
112252.65.188.0/22252.65.188.1 to 252.65.191.254252.65.191.2551,022
113252.65.192.0/22252.65.192.1 to 252.65.195.254252.65.195.2551,022
114252.65.196.0/22252.65.196.1 to 252.65.199.254252.65.199.2551,022
115252.65.200.0/22252.65.200.1 to 252.65.203.254252.65.203.2551,022
116252.65.204.0/22252.65.204.1 to 252.65.207.254252.65.207.2551,022
117252.65.208.0/22252.65.208.1 to 252.65.211.254252.65.211.2551,022
118252.65.212.0/22252.65.212.1 to 252.65.215.254252.65.215.2551,022
119252.65.216.0/22252.65.216.1 to 252.65.219.254252.65.219.2551,022
120252.65.220.0/22252.65.220.1 to 252.65.223.254252.65.223.2551,022
121252.65.224.0/22252.65.224.1 to 252.65.227.254252.65.227.2551,022
122252.65.228.0/22252.65.228.1 to 252.65.231.254252.65.231.2551,022
123252.65.232.0/22252.65.232.1 to 252.65.235.254252.65.235.2551,022
124252.65.236.0/22252.65.236.1 to 252.65.239.254252.65.239.2551,022
125252.65.240.0/22252.65.240.1 to 252.65.243.254252.65.243.2551,022
126252.65.244.0/22252.65.244.1 to 252.65.247.254252.65.247.2551,022
127252.65.248.0/22252.65.248.1 to 252.65.251.254252.65.251.2551,022
128252.65.252.0/22252.65.252.1 to 252.65.255.254252.65.255.2551,022
129252.66.0.0/22252.66.0.1 to 252.66.3.254252.66.3.2551,022
130252.66.4.0/22252.66.4.1 to 252.66.7.254252.66.7.2551,022
131252.66.8.0/22252.66.8.1 to 252.66.11.254252.66.11.2551,022
132252.66.12.0/22252.66.12.1 to 252.66.15.254252.66.15.2551,022
133252.66.16.0/22252.66.16.1 to 252.66.19.254252.66.19.2551,022
134252.66.20.0/22252.66.20.1 to 252.66.23.254252.66.23.2551,022
135252.66.24.0/22252.66.24.1 to 252.66.27.254252.66.27.2551,022
136252.66.28.0/22252.66.28.1 to 252.66.31.254252.66.31.2551,022
137252.66.32.0/22252.66.32.1 to 252.66.35.254252.66.35.2551,022
138252.66.36.0/22252.66.36.1 to 252.66.39.254252.66.39.2551,022
139252.66.40.0/22252.66.40.1 to 252.66.43.254252.66.43.2551,022
140252.66.44.0/22252.66.44.1 to 252.66.47.254252.66.47.2551,022
141252.66.48.0/22252.66.48.1 to 252.66.51.254252.66.51.2551,022
142252.66.52.0/22252.66.52.1 to 252.66.55.254252.66.55.2551,022
143252.66.56.0/22252.66.56.1 to 252.66.59.254252.66.59.2551,022
144252.66.60.0/22252.66.60.1 to 252.66.63.254252.66.63.2551,022
145252.66.64.0/22252.66.64.1 to 252.66.67.254252.66.67.2551,022
146252.66.68.0/22252.66.68.1 to 252.66.71.254252.66.71.2551,022
147252.66.72.0/22252.66.72.1 to 252.66.75.254252.66.75.2551,022
148252.66.76.0/22252.66.76.1 to 252.66.79.254252.66.79.2551,022
149252.66.80.0/22252.66.80.1 to 252.66.83.254252.66.83.2551,022
150252.66.84.0/22252.66.84.1 to 252.66.87.254252.66.87.2551,022
151252.66.88.0/22252.66.88.1 to 252.66.91.254252.66.91.2551,022
152252.66.92.0/22252.66.92.1 to 252.66.95.254252.66.95.2551,022
153252.66.96.0/22252.66.96.1 to 252.66.99.254252.66.99.2551,022
154252.66.100.0/22252.66.100.1 to 252.66.103.254252.66.103.2551,022
155252.66.104.0/22252.66.104.1 to 252.66.107.254252.66.107.2551,022
156252.66.108.0/22252.66.108.1 to 252.66.111.254252.66.111.2551,022
157252.66.112.0/22252.66.112.1 to 252.66.115.254252.66.115.2551,022
158252.66.116.0/22252.66.116.1 to 252.66.119.254252.66.119.2551,022
159252.66.120.0/22252.66.120.1 to 252.66.123.254252.66.123.2551,022
160252.66.124.0/22252.66.124.1 to 252.66.127.254252.66.127.2551,022
161252.66.128.0/22252.66.128.1 to 252.66.131.254252.66.131.2551,022
162252.66.132.0/22252.66.132.1 to 252.66.135.254252.66.135.2551,022
163252.66.136.0/22252.66.136.1 to 252.66.139.254252.66.139.2551,022
164252.66.140.0/22252.66.140.1 to 252.66.143.254252.66.143.2551,022
165252.66.144.0/22252.66.144.1 to 252.66.147.254252.66.147.2551,022
166252.66.148.0/22252.66.148.1 to 252.66.151.254252.66.151.2551,022
167252.66.152.0/22252.66.152.1 to 252.66.155.254252.66.155.2551,022
168252.66.156.0/22252.66.156.1 to 252.66.159.254252.66.159.2551,022
169252.66.160.0/22252.66.160.1 to 252.66.163.254252.66.163.2551,022
170252.66.164.0/22252.66.164.1 to 252.66.167.254252.66.167.2551,022
171252.66.168.0/22252.66.168.1 to 252.66.171.254252.66.171.2551,022
172252.66.172.0/22252.66.172.1 to 252.66.175.254252.66.175.2551,022
173252.66.176.0/22252.66.176.1 to 252.66.179.254252.66.179.2551,022
174252.66.180.0/22252.66.180.1 to 252.66.183.254252.66.183.2551,022
175252.66.184.0/22252.66.184.1 to 252.66.187.254252.66.187.2551,022
176252.66.188.0/22252.66.188.1 to 252.66.191.254252.66.191.2551,022
177252.66.192.0/22252.66.192.1 to 252.66.195.254252.66.195.2551,022
178252.66.196.0/22252.66.196.1 to 252.66.199.254252.66.199.2551,022
179252.66.200.0/22252.66.200.1 to 252.66.203.254252.66.203.2551,022
180252.66.204.0/22252.66.204.1 to 252.66.207.254252.66.207.2551,022
181252.66.208.0/22252.66.208.1 to 252.66.211.254252.66.211.2551,022
182252.66.212.0/22252.66.212.1 to 252.66.215.254252.66.215.2551,022
183252.66.216.0/22252.66.216.1 to 252.66.219.254252.66.219.2551,022
184252.66.220.0/22252.66.220.1 to 252.66.223.254252.66.223.2551,022
185252.66.224.0/22252.66.224.1 to 252.66.227.254252.66.227.2551,022
186252.66.228.0/22252.66.228.1 to 252.66.231.254252.66.231.2551,022
187252.66.232.0/22252.66.232.1 to 252.66.235.254252.66.235.2551,022
188252.66.236.0/22252.66.236.1 to 252.66.239.254252.66.239.2551,022
189252.66.240.0/22252.66.240.1 to 252.66.243.254252.66.243.2551,022
190252.66.244.0/22252.66.244.1 to 252.66.247.254252.66.247.2551,022
191252.66.248.0/22252.66.248.1 to 252.66.251.254252.66.251.2551,022
192252.66.252.0/22252.66.252.1 to 252.66.255.254252.66.255.2551,022
193252.67.0.0/22252.67.0.1 to 252.67.3.254252.67.3.2551,022
194252.67.4.0/22252.67.4.1 to 252.67.7.254252.67.7.2551,022
195252.67.8.0/22252.67.8.1 to 252.67.11.254252.67.11.2551,022
196252.67.12.0/22252.67.12.1 to 252.67.15.254252.67.15.2551,022
197252.67.16.0/22252.67.16.1 to 252.67.19.254252.67.19.2551,022
198252.67.20.0/22252.67.20.1 to 252.67.23.254252.67.23.2551,022
199252.67.24.0/22252.67.24.1 to 252.67.27.254252.67.27.2551,022
200252.67.28.0/22252.67.28.1 to 252.67.31.254252.67.31.2551,022
201252.67.32.0/22252.67.32.1 to 252.67.35.254252.67.35.2551,022
202252.67.36.0/22252.67.36.1 to 252.67.39.254252.67.39.2551,022
203252.67.40.0/22252.67.40.1 to 252.67.43.254252.67.43.2551,022
204252.67.44.0/22252.67.44.1 to 252.67.47.254252.67.47.2551,022
205252.67.48.0/22252.67.48.1 to 252.67.51.254252.67.51.2551,022
206252.67.52.0/22252.67.52.1 to 252.67.55.254252.67.55.2551,022
207252.67.56.0/22252.67.56.1 to 252.67.59.254252.67.59.2551,022
208252.67.60.0/22252.67.60.1 to 252.67.63.254252.67.63.2551,022
209252.67.64.0/22252.67.64.1 to 252.67.67.254252.67.67.2551,022
210252.67.68.0/22252.67.68.1 to 252.67.71.254252.67.71.2551,022
211252.67.72.0/22252.67.72.1 to 252.67.75.254252.67.75.2551,022
212252.67.76.0/22252.67.76.1 to 252.67.79.254252.67.79.2551,022
213252.67.80.0/22252.67.80.1 to 252.67.83.254252.67.83.2551,022
214252.67.84.0/22252.67.84.1 to 252.67.87.254252.67.87.2551,022
215252.67.88.0/22252.67.88.1 to 252.67.91.254252.67.91.2551,022
216252.67.92.0/22252.67.92.1 to 252.67.95.254252.67.95.2551,022
217252.67.96.0/22252.67.96.1 to 252.67.99.254252.67.99.2551,022
218252.67.100.0/22252.67.100.1 to 252.67.103.254252.67.103.2551,022
219252.67.104.0/22252.67.104.1 to 252.67.107.254252.67.107.2551,022
220252.67.108.0/22252.67.108.1 to 252.67.111.254252.67.111.2551,022
221252.67.112.0/22252.67.112.1 to 252.67.115.254252.67.115.2551,022
222252.67.116.0/22252.67.116.1 to 252.67.119.254252.67.119.2551,022
223252.67.120.0/22252.67.120.1 to 252.67.123.254252.67.123.2551,022
224252.67.124.0/22252.67.124.1 to 252.67.127.254252.67.127.2551,022
225252.67.128.0/22252.67.128.1 to 252.67.131.254252.67.131.2551,022
226252.67.132.0/22252.67.132.1 to 252.67.135.254252.67.135.2551,022
227252.67.136.0/22252.67.136.1 to 252.67.139.254252.67.139.2551,022
228252.67.140.0/22252.67.140.1 to 252.67.143.254252.67.143.2551,022
229252.67.144.0/22252.67.144.1 to 252.67.147.254252.67.147.2551,022
230252.67.148.0/22252.67.148.1 to 252.67.151.254252.67.151.2551,022
231252.67.152.0/22252.67.152.1 to 252.67.155.254252.67.155.2551,022
232252.67.156.0/22252.67.156.1 to 252.67.159.254252.67.159.2551,022
233252.67.160.0/22252.67.160.1 to 252.67.163.254252.67.163.2551,022
234252.67.164.0/22252.67.164.1 to 252.67.167.254252.67.167.2551,022
235252.67.168.0/22252.67.168.1 to 252.67.171.254252.67.171.2551,022
236252.67.172.0/22252.67.172.1 to 252.67.175.254252.67.175.2551,022
237252.67.176.0/22252.67.176.1 to 252.67.179.254252.67.179.2551,022
238252.67.180.0/22252.67.180.1 to 252.67.183.254252.67.183.2551,022
239252.67.184.0/22252.67.184.1 to 252.67.187.254252.67.187.2551,022
240252.67.188.0/22252.67.188.1 to 252.67.191.254252.67.191.2551,022
241252.67.192.0/22252.67.192.1 to 252.67.195.254252.67.195.2551,022
242252.67.196.0/22252.67.196.1 to 252.67.199.254252.67.199.2551,022
243252.67.200.0/22252.67.200.1 to 252.67.203.254252.67.203.2551,022
244252.67.204.0/22252.67.204.1 to 252.67.207.254252.67.207.2551,022
245252.67.208.0/22252.67.208.1 to 252.67.211.254252.67.211.2551,022
246252.67.212.0/22252.67.212.1 to 252.67.215.254252.67.215.2551,022
247252.67.216.0/22252.67.216.1 to 252.67.219.254252.67.219.2551,022
248252.67.220.0/22252.67.220.1 to 252.67.223.254252.67.223.2551,022
249252.67.224.0/22252.67.224.1 to 252.67.227.254252.67.227.2551,022
250252.67.228.0/22252.67.228.1 to 252.67.231.254252.67.231.2551,022
251252.67.232.0/22252.67.232.1 to 252.67.235.254252.67.235.2551,022
252252.67.236.0/22252.67.236.1 to 252.67.239.254252.67.239.2551,022
253252.67.240.0/22252.67.240.1 to 252.67.243.254252.67.243.2551,022
254252.67.244.0/22252.67.244.1 to 252.67.247.254252.67.247.2551,022
255252.67.248.0/22252.67.248.1 to 252.67.251.254252.67.251.2551,022
256252.67.252.0/22252.67.252.1 to 252.67.255.254252.67.255.2551,022

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.