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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.

Network225.224.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
225.224.0.0
Broadcast address
225.255.255.255
First usable
225.224.0.1
Last usable
225.255.255.254
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
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E1E00000 · Integer 3789553664 to 3791650815
Reverse DNS zones
224.225.in-addr.arpa
225.225.in-addr.arpa
226.225.in-addr.arpa
227.225.in-addr.arpa
228.225.in-addr.arpa
229.225.in-addr.arpa
230.225.in-addr.arpa
231.225.in-addr.arpa
232.225.in-addr.arpa
233.225.in-addr.arpa
234.225.in-addr.arpa
235.225.in-addr.arpa
236.225.in-addr.arpa
237.225.in-addr.arpa
238.225.in-addr.arpa
239.225.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
Address11100001.11100000.00000000.00000000225.224.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11100001.11100000.00000000.00000000225.224.0.0
Broadcast11100001.11111111.11111111.11111111225.255.255.255
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)

225.224.0.0/11 makes 2,048 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1225.224.0.0/22225.224.0.1 to 225.224.3.254225.224.3.2551,022
2225.224.4.0/22225.224.4.1 to 225.224.7.254225.224.7.2551,022
3225.224.8.0/22225.224.8.1 to 225.224.11.254225.224.11.2551,022
4225.224.12.0/22225.224.12.1 to 225.224.15.254225.224.15.2551,022
5225.224.16.0/22225.224.16.1 to 225.224.19.254225.224.19.2551,022
6225.224.20.0/22225.224.20.1 to 225.224.23.254225.224.23.2551,022
7225.224.24.0/22225.224.24.1 to 225.224.27.254225.224.27.2551,022
8225.224.28.0/22225.224.28.1 to 225.224.31.254225.224.31.2551,022
9225.224.32.0/22225.224.32.1 to 225.224.35.254225.224.35.2551,022
10225.224.36.0/22225.224.36.1 to 225.224.39.254225.224.39.2551,022
11225.224.40.0/22225.224.40.1 to 225.224.43.254225.224.43.2551,022
12225.224.44.0/22225.224.44.1 to 225.224.47.254225.224.47.2551,022
13225.224.48.0/22225.224.48.1 to 225.224.51.254225.224.51.2551,022
14225.224.52.0/22225.224.52.1 to 225.224.55.254225.224.55.2551,022
15225.224.56.0/22225.224.56.1 to 225.224.59.254225.224.59.2551,022
16225.224.60.0/22225.224.60.1 to 225.224.63.254225.224.63.2551,022
17225.224.64.0/22225.224.64.1 to 225.224.67.254225.224.67.2551,022
18225.224.68.0/22225.224.68.1 to 225.224.71.254225.224.71.2551,022
19225.224.72.0/22225.224.72.1 to 225.224.75.254225.224.75.2551,022
20225.224.76.0/22225.224.76.1 to 225.224.79.254225.224.79.2551,022
21225.224.80.0/22225.224.80.1 to 225.224.83.254225.224.83.2551,022
22225.224.84.0/22225.224.84.1 to 225.224.87.254225.224.87.2551,022
23225.224.88.0/22225.224.88.1 to 225.224.91.254225.224.91.2551,022
24225.224.92.0/22225.224.92.1 to 225.224.95.254225.224.95.2551,022
25225.224.96.0/22225.224.96.1 to 225.224.99.254225.224.99.2551,022
26225.224.100.0/22225.224.100.1 to 225.224.103.254225.224.103.2551,022
27225.224.104.0/22225.224.104.1 to 225.224.107.254225.224.107.2551,022
28225.224.108.0/22225.224.108.1 to 225.224.111.254225.224.111.2551,022
29225.224.112.0/22225.224.112.1 to 225.224.115.254225.224.115.2551,022
30225.224.116.0/22225.224.116.1 to 225.224.119.254225.224.119.2551,022
31225.224.120.0/22225.224.120.1 to 225.224.123.254225.224.123.2551,022
32225.224.124.0/22225.224.124.1 to 225.224.127.254225.224.127.2551,022
33225.224.128.0/22225.224.128.1 to 225.224.131.254225.224.131.2551,022
34225.224.132.0/22225.224.132.1 to 225.224.135.254225.224.135.2551,022
35225.224.136.0/22225.224.136.1 to 225.224.139.254225.224.139.2551,022
36225.224.140.0/22225.224.140.1 to 225.224.143.254225.224.143.2551,022
37225.224.144.0/22225.224.144.1 to 225.224.147.254225.224.147.2551,022
38225.224.148.0/22225.224.148.1 to 225.224.151.254225.224.151.2551,022
39225.224.152.0/22225.224.152.1 to 225.224.155.254225.224.155.2551,022
40225.224.156.0/22225.224.156.1 to 225.224.159.254225.224.159.2551,022
41225.224.160.0/22225.224.160.1 to 225.224.163.254225.224.163.2551,022
42225.224.164.0/22225.224.164.1 to 225.224.167.254225.224.167.2551,022
43225.224.168.0/22225.224.168.1 to 225.224.171.254225.224.171.2551,022
44225.224.172.0/22225.224.172.1 to 225.224.175.254225.224.175.2551,022
45225.224.176.0/22225.224.176.1 to 225.224.179.254225.224.179.2551,022
46225.224.180.0/22225.224.180.1 to 225.224.183.254225.224.183.2551,022
47225.224.184.0/22225.224.184.1 to 225.224.187.254225.224.187.2551,022
48225.224.188.0/22225.224.188.1 to 225.224.191.254225.224.191.2551,022
49225.224.192.0/22225.224.192.1 to 225.224.195.254225.224.195.2551,022
50225.224.196.0/22225.224.196.1 to 225.224.199.254225.224.199.2551,022
51225.224.200.0/22225.224.200.1 to 225.224.203.254225.224.203.2551,022
52225.224.204.0/22225.224.204.1 to 225.224.207.254225.224.207.2551,022
53225.224.208.0/22225.224.208.1 to 225.224.211.254225.224.211.2551,022
54225.224.212.0/22225.224.212.1 to 225.224.215.254225.224.215.2551,022
55225.224.216.0/22225.224.216.1 to 225.224.219.254225.224.219.2551,022
56225.224.220.0/22225.224.220.1 to 225.224.223.254225.224.223.2551,022
57225.224.224.0/22225.224.224.1 to 225.224.227.254225.224.227.2551,022
58225.224.228.0/22225.224.228.1 to 225.224.231.254225.224.231.2551,022
59225.224.232.0/22225.224.232.1 to 225.224.235.254225.224.235.2551,022
60225.224.236.0/22225.224.236.1 to 225.224.239.254225.224.239.2551,022
61225.224.240.0/22225.224.240.1 to 225.224.243.254225.224.243.2551,022
62225.224.244.0/22225.224.244.1 to 225.224.247.254225.224.247.2551,022
63225.224.248.0/22225.224.248.1 to 225.224.251.254225.224.251.2551,022
64225.224.252.0/22225.224.252.1 to 225.224.255.254225.224.255.2551,022
65225.225.0.0/22225.225.0.1 to 225.225.3.254225.225.3.2551,022
66225.225.4.0/22225.225.4.1 to 225.225.7.254225.225.7.2551,022
67225.225.8.0/22225.225.8.1 to 225.225.11.254225.225.11.2551,022
68225.225.12.0/22225.225.12.1 to 225.225.15.254225.225.15.2551,022
69225.225.16.0/22225.225.16.1 to 225.225.19.254225.225.19.2551,022
70225.225.20.0/22225.225.20.1 to 225.225.23.254225.225.23.2551,022
71225.225.24.0/22225.225.24.1 to 225.225.27.254225.225.27.2551,022
72225.225.28.0/22225.225.28.1 to 225.225.31.254225.225.31.2551,022
73225.225.32.0/22225.225.32.1 to 225.225.35.254225.225.35.2551,022
74225.225.36.0/22225.225.36.1 to 225.225.39.254225.225.39.2551,022
75225.225.40.0/22225.225.40.1 to 225.225.43.254225.225.43.2551,022
76225.225.44.0/22225.225.44.1 to 225.225.47.254225.225.47.2551,022
77225.225.48.0/22225.225.48.1 to 225.225.51.254225.225.51.2551,022
78225.225.52.0/22225.225.52.1 to 225.225.55.254225.225.55.2551,022
79225.225.56.0/22225.225.56.1 to 225.225.59.254225.225.59.2551,022
80225.225.60.0/22225.225.60.1 to 225.225.63.254225.225.63.2551,022
81225.225.64.0/22225.225.64.1 to 225.225.67.254225.225.67.2551,022
82225.225.68.0/22225.225.68.1 to 225.225.71.254225.225.71.2551,022
83225.225.72.0/22225.225.72.1 to 225.225.75.254225.225.75.2551,022
84225.225.76.0/22225.225.76.1 to 225.225.79.254225.225.79.2551,022
85225.225.80.0/22225.225.80.1 to 225.225.83.254225.225.83.2551,022
86225.225.84.0/22225.225.84.1 to 225.225.87.254225.225.87.2551,022
87225.225.88.0/22225.225.88.1 to 225.225.91.254225.225.91.2551,022
88225.225.92.0/22225.225.92.1 to 225.225.95.254225.225.95.2551,022
89225.225.96.0/22225.225.96.1 to 225.225.99.254225.225.99.2551,022
90225.225.100.0/22225.225.100.1 to 225.225.103.254225.225.103.2551,022
91225.225.104.0/22225.225.104.1 to 225.225.107.254225.225.107.2551,022
92225.225.108.0/22225.225.108.1 to 225.225.111.254225.225.111.2551,022
93225.225.112.0/22225.225.112.1 to 225.225.115.254225.225.115.2551,022
94225.225.116.0/22225.225.116.1 to 225.225.119.254225.225.119.2551,022
95225.225.120.0/22225.225.120.1 to 225.225.123.254225.225.123.2551,022
96225.225.124.0/22225.225.124.1 to 225.225.127.254225.225.127.2551,022
97225.225.128.0/22225.225.128.1 to 225.225.131.254225.225.131.2551,022
98225.225.132.0/22225.225.132.1 to 225.225.135.254225.225.135.2551,022
99225.225.136.0/22225.225.136.1 to 225.225.139.254225.225.139.2551,022
100225.225.140.0/22225.225.140.1 to 225.225.143.254225.225.143.2551,022
101225.225.144.0/22225.225.144.1 to 225.225.147.254225.225.147.2551,022
102225.225.148.0/22225.225.148.1 to 225.225.151.254225.225.151.2551,022
103225.225.152.0/22225.225.152.1 to 225.225.155.254225.225.155.2551,022
104225.225.156.0/22225.225.156.1 to 225.225.159.254225.225.159.2551,022
105225.225.160.0/22225.225.160.1 to 225.225.163.254225.225.163.2551,022
106225.225.164.0/22225.225.164.1 to 225.225.167.254225.225.167.2551,022
107225.225.168.0/22225.225.168.1 to 225.225.171.254225.225.171.2551,022
108225.225.172.0/22225.225.172.1 to 225.225.175.254225.225.175.2551,022
109225.225.176.0/22225.225.176.1 to 225.225.179.254225.225.179.2551,022
110225.225.180.0/22225.225.180.1 to 225.225.183.254225.225.183.2551,022
111225.225.184.0/22225.225.184.1 to 225.225.187.254225.225.187.2551,022
112225.225.188.0/22225.225.188.1 to 225.225.191.254225.225.191.2551,022
113225.225.192.0/22225.225.192.1 to 225.225.195.254225.225.195.2551,022
114225.225.196.0/22225.225.196.1 to 225.225.199.254225.225.199.2551,022
115225.225.200.0/22225.225.200.1 to 225.225.203.254225.225.203.2551,022
116225.225.204.0/22225.225.204.1 to 225.225.207.254225.225.207.2551,022
117225.225.208.0/22225.225.208.1 to 225.225.211.254225.225.211.2551,022
118225.225.212.0/22225.225.212.1 to 225.225.215.254225.225.215.2551,022
119225.225.216.0/22225.225.216.1 to 225.225.219.254225.225.219.2551,022
120225.225.220.0/22225.225.220.1 to 225.225.223.254225.225.223.2551,022
121225.225.224.0/22225.225.224.1 to 225.225.227.254225.225.227.2551,022
122225.225.228.0/22225.225.228.1 to 225.225.231.254225.225.231.2551,022
123225.225.232.0/22225.225.232.1 to 225.225.235.254225.225.235.2551,022
124225.225.236.0/22225.225.236.1 to 225.225.239.254225.225.239.2551,022
125225.225.240.0/22225.225.240.1 to 225.225.243.254225.225.243.2551,022
126225.225.244.0/22225.225.244.1 to 225.225.247.254225.225.247.2551,022
127225.225.248.0/22225.225.248.1 to 225.225.251.254225.225.251.2551,022
128225.225.252.0/22225.225.252.1 to 225.225.255.254225.225.255.2551,022
129225.226.0.0/22225.226.0.1 to 225.226.3.254225.226.3.2551,022
130225.226.4.0/22225.226.4.1 to 225.226.7.254225.226.7.2551,022
131225.226.8.0/22225.226.8.1 to 225.226.11.254225.226.11.2551,022
132225.226.12.0/22225.226.12.1 to 225.226.15.254225.226.15.2551,022
133225.226.16.0/22225.226.16.1 to 225.226.19.254225.226.19.2551,022
134225.226.20.0/22225.226.20.1 to 225.226.23.254225.226.23.2551,022
135225.226.24.0/22225.226.24.1 to 225.226.27.254225.226.27.2551,022
136225.226.28.0/22225.226.28.1 to 225.226.31.254225.226.31.2551,022
137225.226.32.0/22225.226.32.1 to 225.226.35.254225.226.35.2551,022
138225.226.36.0/22225.226.36.1 to 225.226.39.254225.226.39.2551,022
139225.226.40.0/22225.226.40.1 to 225.226.43.254225.226.43.2551,022
140225.226.44.0/22225.226.44.1 to 225.226.47.254225.226.47.2551,022
141225.226.48.0/22225.226.48.1 to 225.226.51.254225.226.51.2551,022
142225.226.52.0/22225.226.52.1 to 225.226.55.254225.226.55.2551,022
143225.226.56.0/22225.226.56.1 to 225.226.59.254225.226.59.2551,022
144225.226.60.0/22225.226.60.1 to 225.226.63.254225.226.63.2551,022
145225.226.64.0/22225.226.64.1 to 225.226.67.254225.226.67.2551,022
146225.226.68.0/22225.226.68.1 to 225.226.71.254225.226.71.2551,022
147225.226.72.0/22225.226.72.1 to 225.226.75.254225.226.75.2551,022
148225.226.76.0/22225.226.76.1 to 225.226.79.254225.226.79.2551,022
149225.226.80.0/22225.226.80.1 to 225.226.83.254225.226.83.2551,022
150225.226.84.0/22225.226.84.1 to 225.226.87.254225.226.87.2551,022
151225.226.88.0/22225.226.88.1 to 225.226.91.254225.226.91.2551,022
152225.226.92.0/22225.226.92.1 to 225.226.95.254225.226.95.2551,022
153225.226.96.0/22225.226.96.1 to 225.226.99.254225.226.99.2551,022
154225.226.100.0/22225.226.100.1 to 225.226.103.254225.226.103.2551,022
155225.226.104.0/22225.226.104.1 to 225.226.107.254225.226.107.2551,022
156225.226.108.0/22225.226.108.1 to 225.226.111.254225.226.111.2551,022
157225.226.112.0/22225.226.112.1 to 225.226.115.254225.226.115.2551,022
158225.226.116.0/22225.226.116.1 to 225.226.119.254225.226.119.2551,022
159225.226.120.0/22225.226.120.1 to 225.226.123.254225.226.123.2551,022
160225.226.124.0/22225.226.124.1 to 225.226.127.254225.226.127.2551,022
161225.226.128.0/22225.226.128.1 to 225.226.131.254225.226.131.2551,022
162225.226.132.0/22225.226.132.1 to 225.226.135.254225.226.135.2551,022
163225.226.136.0/22225.226.136.1 to 225.226.139.254225.226.139.2551,022
164225.226.140.0/22225.226.140.1 to 225.226.143.254225.226.143.2551,022
165225.226.144.0/22225.226.144.1 to 225.226.147.254225.226.147.2551,022
166225.226.148.0/22225.226.148.1 to 225.226.151.254225.226.151.2551,022
167225.226.152.0/22225.226.152.1 to 225.226.155.254225.226.155.2551,022
168225.226.156.0/22225.226.156.1 to 225.226.159.254225.226.159.2551,022
169225.226.160.0/22225.226.160.1 to 225.226.163.254225.226.163.2551,022
170225.226.164.0/22225.226.164.1 to 225.226.167.254225.226.167.2551,022
171225.226.168.0/22225.226.168.1 to 225.226.171.254225.226.171.2551,022
172225.226.172.0/22225.226.172.1 to 225.226.175.254225.226.175.2551,022
173225.226.176.0/22225.226.176.1 to 225.226.179.254225.226.179.2551,022
174225.226.180.0/22225.226.180.1 to 225.226.183.254225.226.183.2551,022
175225.226.184.0/22225.226.184.1 to 225.226.187.254225.226.187.2551,022
176225.226.188.0/22225.226.188.1 to 225.226.191.254225.226.191.2551,022
177225.226.192.0/22225.226.192.1 to 225.226.195.254225.226.195.2551,022
178225.226.196.0/22225.226.196.1 to 225.226.199.254225.226.199.2551,022
179225.226.200.0/22225.226.200.1 to 225.226.203.254225.226.203.2551,022
180225.226.204.0/22225.226.204.1 to 225.226.207.254225.226.207.2551,022
181225.226.208.0/22225.226.208.1 to 225.226.211.254225.226.211.2551,022
182225.226.212.0/22225.226.212.1 to 225.226.215.254225.226.215.2551,022
183225.226.216.0/22225.226.216.1 to 225.226.219.254225.226.219.2551,022
184225.226.220.0/22225.226.220.1 to 225.226.223.254225.226.223.2551,022
185225.226.224.0/22225.226.224.1 to 225.226.227.254225.226.227.2551,022
186225.226.228.0/22225.226.228.1 to 225.226.231.254225.226.231.2551,022
187225.226.232.0/22225.226.232.1 to 225.226.235.254225.226.235.2551,022
188225.226.236.0/22225.226.236.1 to 225.226.239.254225.226.239.2551,022
189225.226.240.0/22225.226.240.1 to 225.226.243.254225.226.243.2551,022
190225.226.244.0/22225.226.244.1 to 225.226.247.254225.226.247.2551,022
191225.226.248.0/22225.226.248.1 to 225.226.251.254225.226.251.2551,022
192225.226.252.0/22225.226.252.1 to 225.226.255.254225.226.255.2551,022
193225.227.0.0/22225.227.0.1 to 225.227.3.254225.227.3.2551,022
194225.227.4.0/22225.227.4.1 to 225.227.7.254225.227.7.2551,022
195225.227.8.0/22225.227.8.1 to 225.227.11.254225.227.11.2551,022
196225.227.12.0/22225.227.12.1 to 225.227.15.254225.227.15.2551,022
197225.227.16.0/22225.227.16.1 to 225.227.19.254225.227.19.2551,022
198225.227.20.0/22225.227.20.1 to 225.227.23.254225.227.23.2551,022
199225.227.24.0/22225.227.24.1 to 225.227.27.254225.227.27.2551,022
200225.227.28.0/22225.227.28.1 to 225.227.31.254225.227.31.2551,022
201225.227.32.0/22225.227.32.1 to 225.227.35.254225.227.35.2551,022
202225.227.36.0/22225.227.36.1 to 225.227.39.254225.227.39.2551,022
203225.227.40.0/22225.227.40.1 to 225.227.43.254225.227.43.2551,022
204225.227.44.0/22225.227.44.1 to 225.227.47.254225.227.47.2551,022
205225.227.48.0/22225.227.48.1 to 225.227.51.254225.227.51.2551,022
206225.227.52.0/22225.227.52.1 to 225.227.55.254225.227.55.2551,022
207225.227.56.0/22225.227.56.1 to 225.227.59.254225.227.59.2551,022
208225.227.60.0/22225.227.60.1 to 225.227.63.254225.227.63.2551,022
209225.227.64.0/22225.227.64.1 to 225.227.67.254225.227.67.2551,022
210225.227.68.0/22225.227.68.1 to 225.227.71.254225.227.71.2551,022
211225.227.72.0/22225.227.72.1 to 225.227.75.254225.227.75.2551,022
212225.227.76.0/22225.227.76.1 to 225.227.79.254225.227.79.2551,022
213225.227.80.0/22225.227.80.1 to 225.227.83.254225.227.83.2551,022
214225.227.84.0/22225.227.84.1 to 225.227.87.254225.227.87.2551,022
215225.227.88.0/22225.227.88.1 to 225.227.91.254225.227.91.2551,022
216225.227.92.0/22225.227.92.1 to 225.227.95.254225.227.95.2551,022
217225.227.96.0/22225.227.96.1 to 225.227.99.254225.227.99.2551,022
218225.227.100.0/22225.227.100.1 to 225.227.103.254225.227.103.2551,022
219225.227.104.0/22225.227.104.1 to 225.227.107.254225.227.107.2551,022
220225.227.108.0/22225.227.108.1 to 225.227.111.254225.227.111.2551,022
221225.227.112.0/22225.227.112.1 to 225.227.115.254225.227.115.2551,022
222225.227.116.0/22225.227.116.1 to 225.227.119.254225.227.119.2551,022
223225.227.120.0/22225.227.120.1 to 225.227.123.254225.227.123.2551,022
224225.227.124.0/22225.227.124.1 to 225.227.127.254225.227.127.2551,022
225225.227.128.0/22225.227.128.1 to 225.227.131.254225.227.131.2551,022
226225.227.132.0/22225.227.132.1 to 225.227.135.254225.227.135.2551,022
227225.227.136.0/22225.227.136.1 to 225.227.139.254225.227.139.2551,022
228225.227.140.0/22225.227.140.1 to 225.227.143.254225.227.143.2551,022
229225.227.144.0/22225.227.144.1 to 225.227.147.254225.227.147.2551,022
230225.227.148.0/22225.227.148.1 to 225.227.151.254225.227.151.2551,022
231225.227.152.0/22225.227.152.1 to 225.227.155.254225.227.155.2551,022
232225.227.156.0/22225.227.156.1 to 225.227.159.254225.227.159.2551,022
233225.227.160.0/22225.227.160.1 to 225.227.163.254225.227.163.2551,022
234225.227.164.0/22225.227.164.1 to 225.227.167.254225.227.167.2551,022
235225.227.168.0/22225.227.168.1 to 225.227.171.254225.227.171.2551,022
236225.227.172.0/22225.227.172.1 to 225.227.175.254225.227.175.2551,022
237225.227.176.0/22225.227.176.1 to 225.227.179.254225.227.179.2551,022
238225.227.180.0/22225.227.180.1 to 225.227.183.254225.227.183.2551,022
239225.227.184.0/22225.227.184.1 to 225.227.187.254225.227.187.2551,022
240225.227.188.0/22225.227.188.1 to 225.227.191.254225.227.191.2551,022
241225.227.192.0/22225.227.192.1 to 225.227.195.254225.227.195.2551,022
242225.227.196.0/22225.227.196.1 to 225.227.199.254225.227.199.2551,022
243225.227.200.0/22225.227.200.1 to 225.227.203.254225.227.203.2551,022
244225.227.204.0/22225.227.204.1 to 225.227.207.254225.227.207.2551,022
245225.227.208.0/22225.227.208.1 to 225.227.211.254225.227.211.2551,022
246225.227.212.0/22225.227.212.1 to 225.227.215.254225.227.215.2551,022
247225.227.216.0/22225.227.216.1 to 225.227.219.254225.227.219.2551,022
248225.227.220.0/22225.227.220.1 to 225.227.223.254225.227.223.2551,022
249225.227.224.0/22225.227.224.1 to 225.227.227.254225.227.227.2551,022
250225.227.228.0/22225.227.228.1 to 225.227.231.254225.227.231.2551,022
251225.227.232.0/22225.227.232.1 to 225.227.235.254225.227.235.2551,022
252225.227.236.0/22225.227.236.1 to 225.227.239.254225.227.239.2551,022
253225.227.240.0/22225.227.240.1 to 225.227.243.254225.227.243.2551,022
254225.227.244.0/22225.227.244.1 to 225.227.247.254225.227.247.2551,022
255225.227.248.0/22225.227.248.1 to 225.227.251.254225.227.251.2551,022
256225.227.252.0/22225.227.252.1 to 225.227.255.254225.227.255.2551,022

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.