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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.

Network226.224.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
226.224.0.0
Broadcast address
226.255.255.255
First usable
226.224.0.1
Last usable
226.255.255.254
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 E2E00000 · Integer 3806330880 to 3808428031
Reverse DNS zones
224.226.in-addr.arpa
225.226.in-addr.arpa
226.226.in-addr.arpa
227.226.in-addr.arpa
228.226.in-addr.arpa
229.226.in-addr.arpa
230.226.in-addr.arpa
231.226.in-addr.arpa
232.226.in-addr.arpa
233.226.in-addr.arpa
234.226.in-addr.arpa
235.226.in-addr.arpa
236.226.in-addr.arpa
237.226.in-addr.arpa
238.226.in-addr.arpa
239.226.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
Address11100010.11100000.00000000.00000000226.224.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11100010.11100000.00000000.00000000226.224.0.0
Broadcast11100010.11111111.11111111.11111111226.255.255.255
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)

226.224.0.0/11 makes 2,048 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.224.0.0/22226.224.0.1 to 226.224.3.254226.224.3.2551,022
2226.224.4.0/22226.224.4.1 to 226.224.7.254226.224.7.2551,022
3226.224.8.0/22226.224.8.1 to 226.224.11.254226.224.11.2551,022
4226.224.12.0/22226.224.12.1 to 226.224.15.254226.224.15.2551,022
5226.224.16.0/22226.224.16.1 to 226.224.19.254226.224.19.2551,022
6226.224.20.0/22226.224.20.1 to 226.224.23.254226.224.23.2551,022
7226.224.24.0/22226.224.24.1 to 226.224.27.254226.224.27.2551,022
8226.224.28.0/22226.224.28.1 to 226.224.31.254226.224.31.2551,022
9226.224.32.0/22226.224.32.1 to 226.224.35.254226.224.35.2551,022
10226.224.36.0/22226.224.36.1 to 226.224.39.254226.224.39.2551,022
11226.224.40.0/22226.224.40.1 to 226.224.43.254226.224.43.2551,022
12226.224.44.0/22226.224.44.1 to 226.224.47.254226.224.47.2551,022
13226.224.48.0/22226.224.48.1 to 226.224.51.254226.224.51.2551,022
14226.224.52.0/22226.224.52.1 to 226.224.55.254226.224.55.2551,022
15226.224.56.0/22226.224.56.1 to 226.224.59.254226.224.59.2551,022
16226.224.60.0/22226.224.60.1 to 226.224.63.254226.224.63.2551,022
17226.224.64.0/22226.224.64.1 to 226.224.67.254226.224.67.2551,022
18226.224.68.0/22226.224.68.1 to 226.224.71.254226.224.71.2551,022
19226.224.72.0/22226.224.72.1 to 226.224.75.254226.224.75.2551,022
20226.224.76.0/22226.224.76.1 to 226.224.79.254226.224.79.2551,022
21226.224.80.0/22226.224.80.1 to 226.224.83.254226.224.83.2551,022
22226.224.84.0/22226.224.84.1 to 226.224.87.254226.224.87.2551,022
23226.224.88.0/22226.224.88.1 to 226.224.91.254226.224.91.2551,022
24226.224.92.0/22226.224.92.1 to 226.224.95.254226.224.95.2551,022
25226.224.96.0/22226.224.96.1 to 226.224.99.254226.224.99.2551,022
26226.224.100.0/22226.224.100.1 to 226.224.103.254226.224.103.2551,022
27226.224.104.0/22226.224.104.1 to 226.224.107.254226.224.107.2551,022
28226.224.108.0/22226.224.108.1 to 226.224.111.254226.224.111.2551,022
29226.224.112.0/22226.224.112.1 to 226.224.115.254226.224.115.2551,022
30226.224.116.0/22226.224.116.1 to 226.224.119.254226.224.119.2551,022
31226.224.120.0/22226.224.120.1 to 226.224.123.254226.224.123.2551,022
32226.224.124.0/22226.224.124.1 to 226.224.127.254226.224.127.2551,022
33226.224.128.0/22226.224.128.1 to 226.224.131.254226.224.131.2551,022
34226.224.132.0/22226.224.132.1 to 226.224.135.254226.224.135.2551,022
35226.224.136.0/22226.224.136.1 to 226.224.139.254226.224.139.2551,022
36226.224.140.0/22226.224.140.1 to 226.224.143.254226.224.143.2551,022
37226.224.144.0/22226.224.144.1 to 226.224.147.254226.224.147.2551,022
38226.224.148.0/22226.224.148.1 to 226.224.151.254226.224.151.2551,022
39226.224.152.0/22226.224.152.1 to 226.224.155.254226.224.155.2551,022
40226.224.156.0/22226.224.156.1 to 226.224.159.254226.224.159.2551,022
41226.224.160.0/22226.224.160.1 to 226.224.163.254226.224.163.2551,022
42226.224.164.0/22226.224.164.1 to 226.224.167.254226.224.167.2551,022
43226.224.168.0/22226.224.168.1 to 226.224.171.254226.224.171.2551,022
44226.224.172.0/22226.224.172.1 to 226.224.175.254226.224.175.2551,022
45226.224.176.0/22226.224.176.1 to 226.224.179.254226.224.179.2551,022
46226.224.180.0/22226.224.180.1 to 226.224.183.254226.224.183.2551,022
47226.224.184.0/22226.224.184.1 to 226.224.187.254226.224.187.2551,022
48226.224.188.0/22226.224.188.1 to 226.224.191.254226.224.191.2551,022
49226.224.192.0/22226.224.192.1 to 226.224.195.254226.224.195.2551,022
50226.224.196.0/22226.224.196.1 to 226.224.199.254226.224.199.2551,022
51226.224.200.0/22226.224.200.1 to 226.224.203.254226.224.203.2551,022
52226.224.204.0/22226.224.204.1 to 226.224.207.254226.224.207.2551,022
53226.224.208.0/22226.224.208.1 to 226.224.211.254226.224.211.2551,022
54226.224.212.0/22226.224.212.1 to 226.224.215.254226.224.215.2551,022
55226.224.216.0/22226.224.216.1 to 226.224.219.254226.224.219.2551,022
56226.224.220.0/22226.224.220.1 to 226.224.223.254226.224.223.2551,022
57226.224.224.0/22226.224.224.1 to 226.224.227.254226.224.227.2551,022
58226.224.228.0/22226.224.228.1 to 226.224.231.254226.224.231.2551,022
59226.224.232.0/22226.224.232.1 to 226.224.235.254226.224.235.2551,022
60226.224.236.0/22226.224.236.1 to 226.224.239.254226.224.239.2551,022
61226.224.240.0/22226.224.240.1 to 226.224.243.254226.224.243.2551,022
62226.224.244.0/22226.224.244.1 to 226.224.247.254226.224.247.2551,022
63226.224.248.0/22226.224.248.1 to 226.224.251.254226.224.251.2551,022
64226.224.252.0/22226.224.252.1 to 226.224.255.254226.224.255.2551,022
65226.225.0.0/22226.225.0.1 to 226.225.3.254226.225.3.2551,022
66226.225.4.0/22226.225.4.1 to 226.225.7.254226.225.7.2551,022
67226.225.8.0/22226.225.8.1 to 226.225.11.254226.225.11.2551,022
68226.225.12.0/22226.225.12.1 to 226.225.15.254226.225.15.2551,022
69226.225.16.0/22226.225.16.1 to 226.225.19.254226.225.19.2551,022
70226.225.20.0/22226.225.20.1 to 226.225.23.254226.225.23.2551,022
71226.225.24.0/22226.225.24.1 to 226.225.27.254226.225.27.2551,022
72226.225.28.0/22226.225.28.1 to 226.225.31.254226.225.31.2551,022
73226.225.32.0/22226.225.32.1 to 226.225.35.254226.225.35.2551,022
74226.225.36.0/22226.225.36.1 to 226.225.39.254226.225.39.2551,022
75226.225.40.0/22226.225.40.1 to 226.225.43.254226.225.43.2551,022
76226.225.44.0/22226.225.44.1 to 226.225.47.254226.225.47.2551,022
77226.225.48.0/22226.225.48.1 to 226.225.51.254226.225.51.2551,022
78226.225.52.0/22226.225.52.1 to 226.225.55.254226.225.55.2551,022
79226.225.56.0/22226.225.56.1 to 226.225.59.254226.225.59.2551,022
80226.225.60.0/22226.225.60.1 to 226.225.63.254226.225.63.2551,022
81226.225.64.0/22226.225.64.1 to 226.225.67.254226.225.67.2551,022
82226.225.68.0/22226.225.68.1 to 226.225.71.254226.225.71.2551,022
83226.225.72.0/22226.225.72.1 to 226.225.75.254226.225.75.2551,022
84226.225.76.0/22226.225.76.1 to 226.225.79.254226.225.79.2551,022
85226.225.80.0/22226.225.80.1 to 226.225.83.254226.225.83.2551,022
86226.225.84.0/22226.225.84.1 to 226.225.87.254226.225.87.2551,022
87226.225.88.0/22226.225.88.1 to 226.225.91.254226.225.91.2551,022
88226.225.92.0/22226.225.92.1 to 226.225.95.254226.225.95.2551,022
89226.225.96.0/22226.225.96.1 to 226.225.99.254226.225.99.2551,022
90226.225.100.0/22226.225.100.1 to 226.225.103.254226.225.103.2551,022
91226.225.104.0/22226.225.104.1 to 226.225.107.254226.225.107.2551,022
92226.225.108.0/22226.225.108.1 to 226.225.111.254226.225.111.2551,022
93226.225.112.0/22226.225.112.1 to 226.225.115.254226.225.115.2551,022
94226.225.116.0/22226.225.116.1 to 226.225.119.254226.225.119.2551,022
95226.225.120.0/22226.225.120.1 to 226.225.123.254226.225.123.2551,022
96226.225.124.0/22226.225.124.1 to 226.225.127.254226.225.127.2551,022
97226.225.128.0/22226.225.128.1 to 226.225.131.254226.225.131.2551,022
98226.225.132.0/22226.225.132.1 to 226.225.135.254226.225.135.2551,022
99226.225.136.0/22226.225.136.1 to 226.225.139.254226.225.139.2551,022
100226.225.140.0/22226.225.140.1 to 226.225.143.254226.225.143.2551,022
101226.225.144.0/22226.225.144.1 to 226.225.147.254226.225.147.2551,022
102226.225.148.0/22226.225.148.1 to 226.225.151.254226.225.151.2551,022
103226.225.152.0/22226.225.152.1 to 226.225.155.254226.225.155.2551,022
104226.225.156.0/22226.225.156.1 to 226.225.159.254226.225.159.2551,022
105226.225.160.0/22226.225.160.1 to 226.225.163.254226.225.163.2551,022
106226.225.164.0/22226.225.164.1 to 226.225.167.254226.225.167.2551,022
107226.225.168.0/22226.225.168.1 to 226.225.171.254226.225.171.2551,022
108226.225.172.0/22226.225.172.1 to 226.225.175.254226.225.175.2551,022
109226.225.176.0/22226.225.176.1 to 226.225.179.254226.225.179.2551,022
110226.225.180.0/22226.225.180.1 to 226.225.183.254226.225.183.2551,022
111226.225.184.0/22226.225.184.1 to 226.225.187.254226.225.187.2551,022
112226.225.188.0/22226.225.188.1 to 226.225.191.254226.225.191.2551,022
113226.225.192.0/22226.225.192.1 to 226.225.195.254226.225.195.2551,022
114226.225.196.0/22226.225.196.1 to 226.225.199.254226.225.199.2551,022
115226.225.200.0/22226.225.200.1 to 226.225.203.254226.225.203.2551,022
116226.225.204.0/22226.225.204.1 to 226.225.207.254226.225.207.2551,022
117226.225.208.0/22226.225.208.1 to 226.225.211.254226.225.211.2551,022
118226.225.212.0/22226.225.212.1 to 226.225.215.254226.225.215.2551,022
119226.225.216.0/22226.225.216.1 to 226.225.219.254226.225.219.2551,022
120226.225.220.0/22226.225.220.1 to 226.225.223.254226.225.223.2551,022
121226.225.224.0/22226.225.224.1 to 226.225.227.254226.225.227.2551,022
122226.225.228.0/22226.225.228.1 to 226.225.231.254226.225.231.2551,022
123226.225.232.0/22226.225.232.1 to 226.225.235.254226.225.235.2551,022
124226.225.236.0/22226.225.236.1 to 226.225.239.254226.225.239.2551,022
125226.225.240.0/22226.225.240.1 to 226.225.243.254226.225.243.2551,022
126226.225.244.0/22226.225.244.1 to 226.225.247.254226.225.247.2551,022
127226.225.248.0/22226.225.248.1 to 226.225.251.254226.225.251.2551,022
128226.225.252.0/22226.225.252.1 to 226.225.255.254226.225.255.2551,022
129226.226.0.0/22226.226.0.1 to 226.226.3.254226.226.3.2551,022
130226.226.4.0/22226.226.4.1 to 226.226.7.254226.226.7.2551,022
131226.226.8.0/22226.226.8.1 to 226.226.11.254226.226.11.2551,022
132226.226.12.0/22226.226.12.1 to 226.226.15.254226.226.15.2551,022
133226.226.16.0/22226.226.16.1 to 226.226.19.254226.226.19.2551,022
134226.226.20.0/22226.226.20.1 to 226.226.23.254226.226.23.2551,022
135226.226.24.0/22226.226.24.1 to 226.226.27.254226.226.27.2551,022
136226.226.28.0/22226.226.28.1 to 226.226.31.254226.226.31.2551,022
137226.226.32.0/22226.226.32.1 to 226.226.35.254226.226.35.2551,022
138226.226.36.0/22226.226.36.1 to 226.226.39.254226.226.39.2551,022
139226.226.40.0/22226.226.40.1 to 226.226.43.254226.226.43.2551,022
140226.226.44.0/22226.226.44.1 to 226.226.47.254226.226.47.2551,022
141226.226.48.0/22226.226.48.1 to 226.226.51.254226.226.51.2551,022
142226.226.52.0/22226.226.52.1 to 226.226.55.254226.226.55.2551,022
143226.226.56.0/22226.226.56.1 to 226.226.59.254226.226.59.2551,022
144226.226.60.0/22226.226.60.1 to 226.226.63.254226.226.63.2551,022
145226.226.64.0/22226.226.64.1 to 226.226.67.254226.226.67.2551,022
146226.226.68.0/22226.226.68.1 to 226.226.71.254226.226.71.2551,022
147226.226.72.0/22226.226.72.1 to 226.226.75.254226.226.75.2551,022
148226.226.76.0/22226.226.76.1 to 226.226.79.254226.226.79.2551,022
149226.226.80.0/22226.226.80.1 to 226.226.83.254226.226.83.2551,022
150226.226.84.0/22226.226.84.1 to 226.226.87.254226.226.87.2551,022
151226.226.88.0/22226.226.88.1 to 226.226.91.254226.226.91.2551,022
152226.226.92.0/22226.226.92.1 to 226.226.95.254226.226.95.2551,022
153226.226.96.0/22226.226.96.1 to 226.226.99.254226.226.99.2551,022
154226.226.100.0/22226.226.100.1 to 226.226.103.254226.226.103.2551,022
155226.226.104.0/22226.226.104.1 to 226.226.107.254226.226.107.2551,022
156226.226.108.0/22226.226.108.1 to 226.226.111.254226.226.111.2551,022
157226.226.112.0/22226.226.112.1 to 226.226.115.254226.226.115.2551,022
158226.226.116.0/22226.226.116.1 to 226.226.119.254226.226.119.2551,022
159226.226.120.0/22226.226.120.1 to 226.226.123.254226.226.123.2551,022
160226.226.124.0/22226.226.124.1 to 226.226.127.254226.226.127.2551,022
161226.226.128.0/22226.226.128.1 to 226.226.131.254226.226.131.2551,022
162226.226.132.0/22226.226.132.1 to 226.226.135.254226.226.135.2551,022
163226.226.136.0/22226.226.136.1 to 226.226.139.254226.226.139.2551,022
164226.226.140.0/22226.226.140.1 to 226.226.143.254226.226.143.2551,022
165226.226.144.0/22226.226.144.1 to 226.226.147.254226.226.147.2551,022
166226.226.148.0/22226.226.148.1 to 226.226.151.254226.226.151.2551,022
167226.226.152.0/22226.226.152.1 to 226.226.155.254226.226.155.2551,022
168226.226.156.0/22226.226.156.1 to 226.226.159.254226.226.159.2551,022
169226.226.160.0/22226.226.160.1 to 226.226.163.254226.226.163.2551,022
170226.226.164.0/22226.226.164.1 to 226.226.167.254226.226.167.2551,022
171226.226.168.0/22226.226.168.1 to 226.226.171.254226.226.171.2551,022
172226.226.172.0/22226.226.172.1 to 226.226.175.254226.226.175.2551,022
173226.226.176.0/22226.226.176.1 to 226.226.179.254226.226.179.2551,022
174226.226.180.0/22226.226.180.1 to 226.226.183.254226.226.183.2551,022
175226.226.184.0/22226.226.184.1 to 226.226.187.254226.226.187.2551,022
176226.226.188.0/22226.226.188.1 to 226.226.191.254226.226.191.2551,022
177226.226.192.0/22226.226.192.1 to 226.226.195.254226.226.195.2551,022
178226.226.196.0/22226.226.196.1 to 226.226.199.254226.226.199.2551,022
179226.226.200.0/22226.226.200.1 to 226.226.203.254226.226.203.2551,022
180226.226.204.0/22226.226.204.1 to 226.226.207.254226.226.207.2551,022
181226.226.208.0/22226.226.208.1 to 226.226.211.254226.226.211.2551,022
182226.226.212.0/22226.226.212.1 to 226.226.215.254226.226.215.2551,022
183226.226.216.0/22226.226.216.1 to 226.226.219.254226.226.219.2551,022
184226.226.220.0/22226.226.220.1 to 226.226.223.254226.226.223.2551,022
185226.226.224.0/22226.226.224.1 to 226.226.227.254226.226.227.2551,022
186226.226.228.0/22226.226.228.1 to 226.226.231.254226.226.231.2551,022
187226.226.232.0/22226.226.232.1 to 226.226.235.254226.226.235.2551,022
188226.226.236.0/22226.226.236.1 to 226.226.239.254226.226.239.2551,022
189226.226.240.0/22226.226.240.1 to 226.226.243.254226.226.243.2551,022
190226.226.244.0/22226.226.244.1 to 226.226.247.254226.226.247.2551,022
191226.226.248.0/22226.226.248.1 to 226.226.251.254226.226.251.2551,022
192226.226.252.0/22226.226.252.1 to 226.226.255.254226.226.255.2551,022
193226.227.0.0/22226.227.0.1 to 226.227.3.254226.227.3.2551,022
194226.227.4.0/22226.227.4.1 to 226.227.7.254226.227.7.2551,022
195226.227.8.0/22226.227.8.1 to 226.227.11.254226.227.11.2551,022
196226.227.12.0/22226.227.12.1 to 226.227.15.254226.227.15.2551,022
197226.227.16.0/22226.227.16.1 to 226.227.19.254226.227.19.2551,022
198226.227.20.0/22226.227.20.1 to 226.227.23.254226.227.23.2551,022
199226.227.24.0/22226.227.24.1 to 226.227.27.254226.227.27.2551,022
200226.227.28.0/22226.227.28.1 to 226.227.31.254226.227.31.2551,022
201226.227.32.0/22226.227.32.1 to 226.227.35.254226.227.35.2551,022
202226.227.36.0/22226.227.36.1 to 226.227.39.254226.227.39.2551,022
203226.227.40.0/22226.227.40.1 to 226.227.43.254226.227.43.2551,022
204226.227.44.0/22226.227.44.1 to 226.227.47.254226.227.47.2551,022
205226.227.48.0/22226.227.48.1 to 226.227.51.254226.227.51.2551,022
206226.227.52.0/22226.227.52.1 to 226.227.55.254226.227.55.2551,022
207226.227.56.0/22226.227.56.1 to 226.227.59.254226.227.59.2551,022
208226.227.60.0/22226.227.60.1 to 226.227.63.254226.227.63.2551,022
209226.227.64.0/22226.227.64.1 to 226.227.67.254226.227.67.2551,022
210226.227.68.0/22226.227.68.1 to 226.227.71.254226.227.71.2551,022
211226.227.72.0/22226.227.72.1 to 226.227.75.254226.227.75.2551,022
212226.227.76.0/22226.227.76.1 to 226.227.79.254226.227.79.2551,022
213226.227.80.0/22226.227.80.1 to 226.227.83.254226.227.83.2551,022
214226.227.84.0/22226.227.84.1 to 226.227.87.254226.227.87.2551,022
215226.227.88.0/22226.227.88.1 to 226.227.91.254226.227.91.2551,022
216226.227.92.0/22226.227.92.1 to 226.227.95.254226.227.95.2551,022
217226.227.96.0/22226.227.96.1 to 226.227.99.254226.227.99.2551,022
218226.227.100.0/22226.227.100.1 to 226.227.103.254226.227.103.2551,022
219226.227.104.0/22226.227.104.1 to 226.227.107.254226.227.107.2551,022
220226.227.108.0/22226.227.108.1 to 226.227.111.254226.227.111.2551,022
221226.227.112.0/22226.227.112.1 to 226.227.115.254226.227.115.2551,022
222226.227.116.0/22226.227.116.1 to 226.227.119.254226.227.119.2551,022
223226.227.120.0/22226.227.120.1 to 226.227.123.254226.227.123.2551,022
224226.227.124.0/22226.227.124.1 to 226.227.127.254226.227.127.2551,022
225226.227.128.0/22226.227.128.1 to 226.227.131.254226.227.131.2551,022
226226.227.132.0/22226.227.132.1 to 226.227.135.254226.227.135.2551,022
227226.227.136.0/22226.227.136.1 to 226.227.139.254226.227.139.2551,022
228226.227.140.0/22226.227.140.1 to 226.227.143.254226.227.143.2551,022
229226.227.144.0/22226.227.144.1 to 226.227.147.254226.227.147.2551,022
230226.227.148.0/22226.227.148.1 to 226.227.151.254226.227.151.2551,022
231226.227.152.0/22226.227.152.1 to 226.227.155.254226.227.155.2551,022
232226.227.156.0/22226.227.156.1 to 226.227.159.254226.227.159.2551,022
233226.227.160.0/22226.227.160.1 to 226.227.163.254226.227.163.2551,022
234226.227.164.0/22226.227.164.1 to 226.227.167.254226.227.167.2551,022
235226.227.168.0/22226.227.168.1 to 226.227.171.254226.227.171.2551,022
236226.227.172.0/22226.227.172.1 to 226.227.175.254226.227.175.2551,022
237226.227.176.0/22226.227.176.1 to 226.227.179.254226.227.179.2551,022
238226.227.180.0/22226.227.180.1 to 226.227.183.254226.227.183.2551,022
239226.227.184.0/22226.227.184.1 to 226.227.187.254226.227.187.2551,022
240226.227.188.0/22226.227.188.1 to 226.227.191.254226.227.191.2551,022
241226.227.192.0/22226.227.192.1 to 226.227.195.254226.227.195.2551,022
242226.227.196.0/22226.227.196.1 to 226.227.199.254226.227.199.2551,022
243226.227.200.0/22226.227.200.1 to 226.227.203.254226.227.203.2551,022
244226.227.204.0/22226.227.204.1 to 226.227.207.254226.227.207.2551,022
245226.227.208.0/22226.227.208.1 to 226.227.211.254226.227.211.2551,022
246226.227.212.0/22226.227.212.1 to 226.227.215.254226.227.215.2551,022
247226.227.216.0/22226.227.216.1 to 226.227.219.254226.227.219.2551,022
248226.227.220.0/22226.227.220.1 to 226.227.223.254226.227.223.2551,022
249226.227.224.0/22226.227.224.1 to 226.227.227.254226.227.227.2551,022
250226.227.228.0/22226.227.228.1 to 226.227.231.254226.227.231.2551,022
251226.227.232.0/22226.227.232.1 to 226.227.235.254226.227.235.2551,022
252226.227.236.0/22226.227.236.1 to 226.227.239.254226.227.239.2551,022
253226.227.240.0/22226.227.240.1 to 226.227.243.254226.227.243.2551,022
254226.227.244.0/22226.227.244.1 to 226.227.247.254226.227.247.2551,022
255226.227.248.0/22226.227.248.1 to 226.227.251.254226.227.251.2551,022
256226.227.252.0/22226.227.252.1 to 226.227.255.254226.227.255.2551,022

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.