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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/21
/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 1,024 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.224.0.0/21226.224.0.1 to 226.224.7.254226.224.7.2552,046
2226.224.8.0/21226.224.8.1 to 226.224.15.254226.224.15.2552,046
3226.224.16.0/21226.224.16.1 to 226.224.23.254226.224.23.2552,046
4226.224.24.0/21226.224.24.1 to 226.224.31.254226.224.31.2552,046
5226.224.32.0/21226.224.32.1 to 226.224.39.254226.224.39.2552,046
6226.224.40.0/21226.224.40.1 to 226.224.47.254226.224.47.2552,046
7226.224.48.0/21226.224.48.1 to 226.224.55.254226.224.55.2552,046
8226.224.56.0/21226.224.56.1 to 226.224.63.254226.224.63.2552,046
9226.224.64.0/21226.224.64.1 to 226.224.71.254226.224.71.2552,046
10226.224.72.0/21226.224.72.1 to 226.224.79.254226.224.79.2552,046
11226.224.80.0/21226.224.80.1 to 226.224.87.254226.224.87.2552,046
12226.224.88.0/21226.224.88.1 to 226.224.95.254226.224.95.2552,046
13226.224.96.0/21226.224.96.1 to 226.224.103.254226.224.103.2552,046
14226.224.104.0/21226.224.104.1 to 226.224.111.254226.224.111.2552,046
15226.224.112.0/21226.224.112.1 to 226.224.119.254226.224.119.2552,046
16226.224.120.0/21226.224.120.1 to 226.224.127.254226.224.127.2552,046
17226.224.128.0/21226.224.128.1 to 226.224.135.254226.224.135.2552,046
18226.224.136.0/21226.224.136.1 to 226.224.143.254226.224.143.2552,046
19226.224.144.0/21226.224.144.1 to 226.224.151.254226.224.151.2552,046
20226.224.152.0/21226.224.152.1 to 226.224.159.254226.224.159.2552,046
21226.224.160.0/21226.224.160.1 to 226.224.167.254226.224.167.2552,046
22226.224.168.0/21226.224.168.1 to 226.224.175.254226.224.175.2552,046
23226.224.176.0/21226.224.176.1 to 226.224.183.254226.224.183.2552,046
24226.224.184.0/21226.224.184.1 to 226.224.191.254226.224.191.2552,046
25226.224.192.0/21226.224.192.1 to 226.224.199.254226.224.199.2552,046
26226.224.200.0/21226.224.200.1 to 226.224.207.254226.224.207.2552,046
27226.224.208.0/21226.224.208.1 to 226.224.215.254226.224.215.2552,046
28226.224.216.0/21226.224.216.1 to 226.224.223.254226.224.223.2552,046
29226.224.224.0/21226.224.224.1 to 226.224.231.254226.224.231.2552,046
30226.224.232.0/21226.224.232.1 to 226.224.239.254226.224.239.2552,046
31226.224.240.0/21226.224.240.1 to 226.224.247.254226.224.247.2552,046
32226.224.248.0/21226.224.248.1 to 226.224.255.254226.224.255.2552,046
33226.225.0.0/21226.225.0.1 to 226.225.7.254226.225.7.2552,046
34226.225.8.0/21226.225.8.1 to 226.225.15.254226.225.15.2552,046
35226.225.16.0/21226.225.16.1 to 226.225.23.254226.225.23.2552,046
36226.225.24.0/21226.225.24.1 to 226.225.31.254226.225.31.2552,046
37226.225.32.0/21226.225.32.1 to 226.225.39.254226.225.39.2552,046
38226.225.40.0/21226.225.40.1 to 226.225.47.254226.225.47.2552,046
39226.225.48.0/21226.225.48.1 to 226.225.55.254226.225.55.2552,046
40226.225.56.0/21226.225.56.1 to 226.225.63.254226.225.63.2552,046
41226.225.64.0/21226.225.64.1 to 226.225.71.254226.225.71.2552,046
42226.225.72.0/21226.225.72.1 to 226.225.79.254226.225.79.2552,046
43226.225.80.0/21226.225.80.1 to 226.225.87.254226.225.87.2552,046
44226.225.88.0/21226.225.88.1 to 226.225.95.254226.225.95.2552,046
45226.225.96.0/21226.225.96.1 to 226.225.103.254226.225.103.2552,046
46226.225.104.0/21226.225.104.1 to 226.225.111.254226.225.111.2552,046
47226.225.112.0/21226.225.112.1 to 226.225.119.254226.225.119.2552,046
48226.225.120.0/21226.225.120.1 to 226.225.127.254226.225.127.2552,046
49226.225.128.0/21226.225.128.1 to 226.225.135.254226.225.135.2552,046
50226.225.136.0/21226.225.136.1 to 226.225.143.254226.225.143.2552,046
51226.225.144.0/21226.225.144.1 to 226.225.151.254226.225.151.2552,046
52226.225.152.0/21226.225.152.1 to 226.225.159.254226.225.159.2552,046
53226.225.160.0/21226.225.160.1 to 226.225.167.254226.225.167.2552,046
54226.225.168.0/21226.225.168.1 to 226.225.175.254226.225.175.2552,046
55226.225.176.0/21226.225.176.1 to 226.225.183.254226.225.183.2552,046
56226.225.184.0/21226.225.184.1 to 226.225.191.254226.225.191.2552,046
57226.225.192.0/21226.225.192.1 to 226.225.199.254226.225.199.2552,046
58226.225.200.0/21226.225.200.1 to 226.225.207.254226.225.207.2552,046
59226.225.208.0/21226.225.208.1 to 226.225.215.254226.225.215.2552,046
60226.225.216.0/21226.225.216.1 to 226.225.223.254226.225.223.2552,046
61226.225.224.0/21226.225.224.1 to 226.225.231.254226.225.231.2552,046
62226.225.232.0/21226.225.232.1 to 226.225.239.254226.225.239.2552,046
63226.225.240.0/21226.225.240.1 to 226.225.247.254226.225.247.2552,046
64226.225.248.0/21226.225.248.1 to 226.225.255.254226.225.255.2552,046
65226.226.0.0/21226.226.0.1 to 226.226.7.254226.226.7.2552,046
66226.226.8.0/21226.226.8.1 to 226.226.15.254226.226.15.2552,046
67226.226.16.0/21226.226.16.1 to 226.226.23.254226.226.23.2552,046
68226.226.24.0/21226.226.24.1 to 226.226.31.254226.226.31.2552,046
69226.226.32.0/21226.226.32.1 to 226.226.39.254226.226.39.2552,046
70226.226.40.0/21226.226.40.1 to 226.226.47.254226.226.47.2552,046
71226.226.48.0/21226.226.48.1 to 226.226.55.254226.226.55.2552,046
72226.226.56.0/21226.226.56.1 to 226.226.63.254226.226.63.2552,046
73226.226.64.0/21226.226.64.1 to 226.226.71.254226.226.71.2552,046
74226.226.72.0/21226.226.72.1 to 226.226.79.254226.226.79.2552,046
75226.226.80.0/21226.226.80.1 to 226.226.87.254226.226.87.2552,046
76226.226.88.0/21226.226.88.1 to 226.226.95.254226.226.95.2552,046
77226.226.96.0/21226.226.96.1 to 226.226.103.254226.226.103.2552,046
78226.226.104.0/21226.226.104.1 to 226.226.111.254226.226.111.2552,046
79226.226.112.0/21226.226.112.1 to 226.226.119.254226.226.119.2552,046
80226.226.120.0/21226.226.120.1 to 226.226.127.254226.226.127.2552,046
81226.226.128.0/21226.226.128.1 to 226.226.135.254226.226.135.2552,046
82226.226.136.0/21226.226.136.1 to 226.226.143.254226.226.143.2552,046
83226.226.144.0/21226.226.144.1 to 226.226.151.254226.226.151.2552,046
84226.226.152.0/21226.226.152.1 to 226.226.159.254226.226.159.2552,046
85226.226.160.0/21226.226.160.1 to 226.226.167.254226.226.167.2552,046
86226.226.168.0/21226.226.168.1 to 226.226.175.254226.226.175.2552,046
87226.226.176.0/21226.226.176.1 to 226.226.183.254226.226.183.2552,046
88226.226.184.0/21226.226.184.1 to 226.226.191.254226.226.191.2552,046
89226.226.192.0/21226.226.192.1 to 226.226.199.254226.226.199.2552,046
90226.226.200.0/21226.226.200.1 to 226.226.207.254226.226.207.2552,046
91226.226.208.0/21226.226.208.1 to 226.226.215.254226.226.215.2552,046
92226.226.216.0/21226.226.216.1 to 226.226.223.254226.226.223.2552,046
93226.226.224.0/21226.226.224.1 to 226.226.231.254226.226.231.2552,046
94226.226.232.0/21226.226.232.1 to 226.226.239.254226.226.239.2552,046
95226.226.240.0/21226.226.240.1 to 226.226.247.254226.226.247.2552,046
96226.226.248.0/21226.226.248.1 to 226.226.255.254226.226.255.2552,046
97226.227.0.0/21226.227.0.1 to 226.227.7.254226.227.7.2552,046
98226.227.8.0/21226.227.8.1 to 226.227.15.254226.227.15.2552,046
99226.227.16.0/21226.227.16.1 to 226.227.23.254226.227.23.2552,046
100226.227.24.0/21226.227.24.1 to 226.227.31.254226.227.31.2552,046
101226.227.32.0/21226.227.32.1 to 226.227.39.254226.227.39.2552,046
102226.227.40.0/21226.227.40.1 to 226.227.47.254226.227.47.2552,046
103226.227.48.0/21226.227.48.1 to 226.227.55.254226.227.55.2552,046
104226.227.56.0/21226.227.56.1 to 226.227.63.254226.227.63.2552,046
105226.227.64.0/21226.227.64.1 to 226.227.71.254226.227.71.2552,046
106226.227.72.0/21226.227.72.1 to 226.227.79.254226.227.79.2552,046
107226.227.80.0/21226.227.80.1 to 226.227.87.254226.227.87.2552,046
108226.227.88.0/21226.227.88.1 to 226.227.95.254226.227.95.2552,046
109226.227.96.0/21226.227.96.1 to 226.227.103.254226.227.103.2552,046
110226.227.104.0/21226.227.104.1 to 226.227.111.254226.227.111.2552,046
111226.227.112.0/21226.227.112.1 to 226.227.119.254226.227.119.2552,046
112226.227.120.0/21226.227.120.1 to 226.227.127.254226.227.127.2552,046
113226.227.128.0/21226.227.128.1 to 226.227.135.254226.227.135.2552,046
114226.227.136.0/21226.227.136.1 to 226.227.143.254226.227.143.2552,046
115226.227.144.0/21226.227.144.1 to 226.227.151.254226.227.151.2552,046
116226.227.152.0/21226.227.152.1 to 226.227.159.254226.227.159.2552,046
117226.227.160.0/21226.227.160.1 to 226.227.167.254226.227.167.2552,046
118226.227.168.0/21226.227.168.1 to 226.227.175.254226.227.175.2552,046
119226.227.176.0/21226.227.176.1 to 226.227.183.254226.227.183.2552,046
120226.227.184.0/21226.227.184.1 to 226.227.191.254226.227.191.2552,046
121226.227.192.0/21226.227.192.1 to 226.227.199.254226.227.199.2552,046
122226.227.200.0/21226.227.200.1 to 226.227.207.254226.227.207.2552,046
123226.227.208.0/21226.227.208.1 to 226.227.215.254226.227.215.2552,046
124226.227.216.0/21226.227.216.1 to 226.227.223.254226.227.223.2552,046
125226.227.224.0/21226.227.224.1 to 226.227.231.254226.227.231.2552,046
126226.227.232.0/21226.227.232.1 to 226.227.239.254226.227.239.2552,046
127226.227.240.0/21226.227.240.1 to 226.227.247.254226.227.247.2552,046
128226.227.248.0/21226.227.248.1 to 226.227.255.254226.227.255.2552,046
129226.228.0.0/21226.228.0.1 to 226.228.7.254226.228.7.2552,046
130226.228.8.0/21226.228.8.1 to 226.228.15.254226.228.15.2552,046
131226.228.16.0/21226.228.16.1 to 226.228.23.254226.228.23.2552,046
132226.228.24.0/21226.228.24.1 to 226.228.31.254226.228.31.2552,046
133226.228.32.0/21226.228.32.1 to 226.228.39.254226.228.39.2552,046
134226.228.40.0/21226.228.40.1 to 226.228.47.254226.228.47.2552,046
135226.228.48.0/21226.228.48.1 to 226.228.55.254226.228.55.2552,046
136226.228.56.0/21226.228.56.1 to 226.228.63.254226.228.63.2552,046
137226.228.64.0/21226.228.64.1 to 226.228.71.254226.228.71.2552,046
138226.228.72.0/21226.228.72.1 to 226.228.79.254226.228.79.2552,046
139226.228.80.0/21226.228.80.1 to 226.228.87.254226.228.87.2552,046
140226.228.88.0/21226.228.88.1 to 226.228.95.254226.228.95.2552,046
141226.228.96.0/21226.228.96.1 to 226.228.103.254226.228.103.2552,046
142226.228.104.0/21226.228.104.1 to 226.228.111.254226.228.111.2552,046
143226.228.112.0/21226.228.112.1 to 226.228.119.254226.228.119.2552,046
144226.228.120.0/21226.228.120.1 to 226.228.127.254226.228.127.2552,046
145226.228.128.0/21226.228.128.1 to 226.228.135.254226.228.135.2552,046
146226.228.136.0/21226.228.136.1 to 226.228.143.254226.228.143.2552,046
147226.228.144.0/21226.228.144.1 to 226.228.151.254226.228.151.2552,046
148226.228.152.0/21226.228.152.1 to 226.228.159.254226.228.159.2552,046
149226.228.160.0/21226.228.160.1 to 226.228.167.254226.228.167.2552,046
150226.228.168.0/21226.228.168.1 to 226.228.175.254226.228.175.2552,046
151226.228.176.0/21226.228.176.1 to 226.228.183.254226.228.183.2552,046
152226.228.184.0/21226.228.184.1 to 226.228.191.254226.228.191.2552,046
153226.228.192.0/21226.228.192.1 to 226.228.199.254226.228.199.2552,046
154226.228.200.0/21226.228.200.1 to 226.228.207.254226.228.207.2552,046
155226.228.208.0/21226.228.208.1 to 226.228.215.254226.228.215.2552,046
156226.228.216.0/21226.228.216.1 to 226.228.223.254226.228.223.2552,046
157226.228.224.0/21226.228.224.1 to 226.228.231.254226.228.231.2552,046
158226.228.232.0/21226.228.232.1 to 226.228.239.254226.228.239.2552,046
159226.228.240.0/21226.228.240.1 to 226.228.247.254226.228.247.2552,046
160226.228.248.0/21226.228.248.1 to 226.228.255.254226.228.255.2552,046
161226.229.0.0/21226.229.0.1 to 226.229.7.254226.229.7.2552,046
162226.229.8.0/21226.229.8.1 to 226.229.15.254226.229.15.2552,046
163226.229.16.0/21226.229.16.1 to 226.229.23.254226.229.23.2552,046
164226.229.24.0/21226.229.24.1 to 226.229.31.254226.229.31.2552,046
165226.229.32.0/21226.229.32.1 to 226.229.39.254226.229.39.2552,046
166226.229.40.0/21226.229.40.1 to 226.229.47.254226.229.47.2552,046
167226.229.48.0/21226.229.48.1 to 226.229.55.254226.229.55.2552,046
168226.229.56.0/21226.229.56.1 to 226.229.63.254226.229.63.2552,046
169226.229.64.0/21226.229.64.1 to 226.229.71.254226.229.71.2552,046
170226.229.72.0/21226.229.72.1 to 226.229.79.254226.229.79.2552,046
171226.229.80.0/21226.229.80.1 to 226.229.87.254226.229.87.2552,046
172226.229.88.0/21226.229.88.1 to 226.229.95.254226.229.95.2552,046
173226.229.96.0/21226.229.96.1 to 226.229.103.254226.229.103.2552,046
174226.229.104.0/21226.229.104.1 to 226.229.111.254226.229.111.2552,046
175226.229.112.0/21226.229.112.1 to 226.229.119.254226.229.119.2552,046
176226.229.120.0/21226.229.120.1 to 226.229.127.254226.229.127.2552,046
177226.229.128.0/21226.229.128.1 to 226.229.135.254226.229.135.2552,046
178226.229.136.0/21226.229.136.1 to 226.229.143.254226.229.143.2552,046
179226.229.144.0/21226.229.144.1 to 226.229.151.254226.229.151.2552,046
180226.229.152.0/21226.229.152.1 to 226.229.159.254226.229.159.2552,046
181226.229.160.0/21226.229.160.1 to 226.229.167.254226.229.167.2552,046
182226.229.168.0/21226.229.168.1 to 226.229.175.254226.229.175.2552,046
183226.229.176.0/21226.229.176.1 to 226.229.183.254226.229.183.2552,046
184226.229.184.0/21226.229.184.1 to 226.229.191.254226.229.191.2552,046
185226.229.192.0/21226.229.192.1 to 226.229.199.254226.229.199.2552,046
186226.229.200.0/21226.229.200.1 to 226.229.207.254226.229.207.2552,046
187226.229.208.0/21226.229.208.1 to 226.229.215.254226.229.215.2552,046
188226.229.216.0/21226.229.216.1 to 226.229.223.254226.229.223.2552,046
189226.229.224.0/21226.229.224.1 to 226.229.231.254226.229.231.2552,046
190226.229.232.0/21226.229.232.1 to 226.229.239.254226.229.239.2552,046
191226.229.240.0/21226.229.240.1 to 226.229.247.254226.229.247.2552,046
192226.229.248.0/21226.229.248.1 to 226.229.255.254226.229.255.2552,046
193226.230.0.0/21226.230.0.1 to 226.230.7.254226.230.7.2552,046
194226.230.8.0/21226.230.8.1 to 226.230.15.254226.230.15.2552,046
195226.230.16.0/21226.230.16.1 to 226.230.23.254226.230.23.2552,046
196226.230.24.0/21226.230.24.1 to 226.230.31.254226.230.31.2552,046
197226.230.32.0/21226.230.32.1 to 226.230.39.254226.230.39.2552,046
198226.230.40.0/21226.230.40.1 to 226.230.47.254226.230.47.2552,046
199226.230.48.0/21226.230.48.1 to 226.230.55.254226.230.55.2552,046
200226.230.56.0/21226.230.56.1 to 226.230.63.254226.230.63.2552,046
201226.230.64.0/21226.230.64.1 to 226.230.71.254226.230.71.2552,046
202226.230.72.0/21226.230.72.1 to 226.230.79.254226.230.79.2552,046
203226.230.80.0/21226.230.80.1 to 226.230.87.254226.230.87.2552,046
204226.230.88.0/21226.230.88.1 to 226.230.95.254226.230.95.2552,046
205226.230.96.0/21226.230.96.1 to 226.230.103.254226.230.103.2552,046
206226.230.104.0/21226.230.104.1 to 226.230.111.254226.230.111.2552,046
207226.230.112.0/21226.230.112.1 to 226.230.119.254226.230.119.2552,046
208226.230.120.0/21226.230.120.1 to 226.230.127.254226.230.127.2552,046
209226.230.128.0/21226.230.128.1 to 226.230.135.254226.230.135.2552,046
210226.230.136.0/21226.230.136.1 to 226.230.143.254226.230.143.2552,046
211226.230.144.0/21226.230.144.1 to 226.230.151.254226.230.151.2552,046
212226.230.152.0/21226.230.152.1 to 226.230.159.254226.230.159.2552,046
213226.230.160.0/21226.230.160.1 to 226.230.167.254226.230.167.2552,046
214226.230.168.0/21226.230.168.1 to 226.230.175.254226.230.175.2552,046
215226.230.176.0/21226.230.176.1 to 226.230.183.254226.230.183.2552,046
216226.230.184.0/21226.230.184.1 to 226.230.191.254226.230.191.2552,046
217226.230.192.0/21226.230.192.1 to 226.230.199.254226.230.199.2552,046
218226.230.200.0/21226.230.200.1 to 226.230.207.254226.230.207.2552,046
219226.230.208.0/21226.230.208.1 to 226.230.215.254226.230.215.2552,046
220226.230.216.0/21226.230.216.1 to 226.230.223.254226.230.223.2552,046
221226.230.224.0/21226.230.224.1 to 226.230.231.254226.230.231.2552,046
222226.230.232.0/21226.230.232.1 to 226.230.239.254226.230.239.2552,046
223226.230.240.0/21226.230.240.1 to 226.230.247.254226.230.247.2552,046
224226.230.248.0/21226.230.248.1 to 226.230.255.254226.230.255.2552,046
225226.231.0.0/21226.231.0.1 to 226.231.7.254226.231.7.2552,046
226226.231.8.0/21226.231.8.1 to 226.231.15.254226.231.15.2552,046
227226.231.16.0/21226.231.16.1 to 226.231.23.254226.231.23.2552,046
228226.231.24.0/21226.231.24.1 to 226.231.31.254226.231.31.2552,046
229226.231.32.0/21226.231.32.1 to 226.231.39.254226.231.39.2552,046
230226.231.40.0/21226.231.40.1 to 226.231.47.254226.231.47.2552,046
231226.231.48.0/21226.231.48.1 to 226.231.55.254226.231.55.2552,046
232226.231.56.0/21226.231.56.1 to 226.231.63.254226.231.63.2552,046
233226.231.64.0/21226.231.64.1 to 226.231.71.254226.231.71.2552,046
234226.231.72.0/21226.231.72.1 to 226.231.79.254226.231.79.2552,046
235226.231.80.0/21226.231.80.1 to 226.231.87.254226.231.87.2552,046
236226.231.88.0/21226.231.88.1 to 226.231.95.254226.231.95.2552,046
237226.231.96.0/21226.231.96.1 to 226.231.103.254226.231.103.2552,046
238226.231.104.0/21226.231.104.1 to 226.231.111.254226.231.111.2552,046
239226.231.112.0/21226.231.112.1 to 226.231.119.254226.231.119.2552,046
240226.231.120.0/21226.231.120.1 to 226.231.127.254226.231.127.2552,046
241226.231.128.0/21226.231.128.1 to 226.231.135.254226.231.135.2552,046
242226.231.136.0/21226.231.136.1 to 226.231.143.254226.231.143.2552,046
243226.231.144.0/21226.231.144.1 to 226.231.151.254226.231.151.2552,046
244226.231.152.0/21226.231.152.1 to 226.231.159.254226.231.159.2552,046
245226.231.160.0/21226.231.160.1 to 226.231.167.254226.231.167.2552,046
246226.231.168.0/21226.231.168.1 to 226.231.175.254226.231.175.2552,046
247226.231.176.0/21226.231.176.1 to 226.231.183.254226.231.183.2552,046
248226.231.184.0/21226.231.184.1 to 226.231.191.254226.231.191.2552,046
249226.231.192.0/21226.231.192.1 to 226.231.199.254226.231.199.2552,046
250226.231.200.0/21226.231.200.1 to 226.231.207.254226.231.207.2552,046
251226.231.208.0/21226.231.208.1 to 226.231.215.254226.231.215.2552,046
252226.231.216.0/21226.231.216.1 to 226.231.223.254226.231.223.2552,046
253226.231.224.0/21226.231.224.1 to 226.231.231.254226.231.231.2552,046
254226.231.232.0/21226.231.232.1 to 226.231.239.254226.231.239.2552,046
255226.231.240.0/21226.231.240.1 to 226.231.247.254226.231.247.2552,046
256226.231.248.0/21226.231.248.1 to 226.231.255.254226.231.255.2552,046

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.