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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.

Network234.224.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
234.224.0.0
Broadcast address
234.255.255.255
First usable
234.224.0.1
Last usable
234.255.255.254
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 EAE00000 · Integer 3940548608 to 3942645759
Reverse DNS zones
224.234.in-addr.arpa
225.234.in-addr.arpa
226.234.in-addr.arpa
227.234.in-addr.arpa
228.234.in-addr.arpa
229.234.in-addr.arpa
230.234.in-addr.arpa
231.234.in-addr.arpa
232.234.in-addr.arpa
233.234.in-addr.arpa
234.234.in-addr.arpa
235.234.in-addr.arpa
236.234.in-addr.arpa
237.234.in-addr.arpa
238.234.in-addr.arpa
239.234.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
Address11101010.11100000.00000000.00000000234.224.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11101010.11100000.00000000.00000000234.224.0.0
Broadcast11101010.11111111.11111111.11111111234.255.255.255
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)

234.224.0.0/11 makes 1,024 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1234.224.0.0/21234.224.0.1 to 234.224.7.254234.224.7.2552,046
2234.224.8.0/21234.224.8.1 to 234.224.15.254234.224.15.2552,046
3234.224.16.0/21234.224.16.1 to 234.224.23.254234.224.23.2552,046
4234.224.24.0/21234.224.24.1 to 234.224.31.254234.224.31.2552,046
5234.224.32.0/21234.224.32.1 to 234.224.39.254234.224.39.2552,046
6234.224.40.0/21234.224.40.1 to 234.224.47.254234.224.47.2552,046
7234.224.48.0/21234.224.48.1 to 234.224.55.254234.224.55.2552,046
8234.224.56.0/21234.224.56.1 to 234.224.63.254234.224.63.2552,046
9234.224.64.0/21234.224.64.1 to 234.224.71.254234.224.71.2552,046
10234.224.72.0/21234.224.72.1 to 234.224.79.254234.224.79.2552,046
11234.224.80.0/21234.224.80.1 to 234.224.87.254234.224.87.2552,046
12234.224.88.0/21234.224.88.1 to 234.224.95.254234.224.95.2552,046
13234.224.96.0/21234.224.96.1 to 234.224.103.254234.224.103.2552,046
14234.224.104.0/21234.224.104.1 to 234.224.111.254234.224.111.2552,046
15234.224.112.0/21234.224.112.1 to 234.224.119.254234.224.119.2552,046
16234.224.120.0/21234.224.120.1 to 234.224.127.254234.224.127.2552,046
17234.224.128.0/21234.224.128.1 to 234.224.135.254234.224.135.2552,046
18234.224.136.0/21234.224.136.1 to 234.224.143.254234.224.143.2552,046
19234.224.144.0/21234.224.144.1 to 234.224.151.254234.224.151.2552,046
20234.224.152.0/21234.224.152.1 to 234.224.159.254234.224.159.2552,046
21234.224.160.0/21234.224.160.1 to 234.224.167.254234.224.167.2552,046
22234.224.168.0/21234.224.168.1 to 234.224.175.254234.224.175.2552,046
23234.224.176.0/21234.224.176.1 to 234.224.183.254234.224.183.2552,046
24234.224.184.0/21234.224.184.1 to 234.224.191.254234.224.191.2552,046
25234.224.192.0/21234.224.192.1 to 234.224.199.254234.224.199.2552,046
26234.224.200.0/21234.224.200.1 to 234.224.207.254234.224.207.2552,046
27234.224.208.0/21234.224.208.1 to 234.224.215.254234.224.215.2552,046
28234.224.216.0/21234.224.216.1 to 234.224.223.254234.224.223.2552,046
29234.224.224.0/21234.224.224.1 to 234.224.231.254234.224.231.2552,046
30234.224.232.0/21234.224.232.1 to 234.224.239.254234.224.239.2552,046
31234.224.240.0/21234.224.240.1 to 234.224.247.254234.224.247.2552,046
32234.224.248.0/21234.224.248.1 to 234.224.255.254234.224.255.2552,046
33234.225.0.0/21234.225.0.1 to 234.225.7.254234.225.7.2552,046
34234.225.8.0/21234.225.8.1 to 234.225.15.254234.225.15.2552,046
35234.225.16.0/21234.225.16.1 to 234.225.23.254234.225.23.2552,046
36234.225.24.0/21234.225.24.1 to 234.225.31.254234.225.31.2552,046
37234.225.32.0/21234.225.32.1 to 234.225.39.254234.225.39.2552,046
38234.225.40.0/21234.225.40.1 to 234.225.47.254234.225.47.2552,046
39234.225.48.0/21234.225.48.1 to 234.225.55.254234.225.55.2552,046
40234.225.56.0/21234.225.56.1 to 234.225.63.254234.225.63.2552,046
41234.225.64.0/21234.225.64.1 to 234.225.71.254234.225.71.2552,046
42234.225.72.0/21234.225.72.1 to 234.225.79.254234.225.79.2552,046
43234.225.80.0/21234.225.80.1 to 234.225.87.254234.225.87.2552,046
44234.225.88.0/21234.225.88.1 to 234.225.95.254234.225.95.2552,046
45234.225.96.0/21234.225.96.1 to 234.225.103.254234.225.103.2552,046
46234.225.104.0/21234.225.104.1 to 234.225.111.254234.225.111.2552,046
47234.225.112.0/21234.225.112.1 to 234.225.119.254234.225.119.2552,046
48234.225.120.0/21234.225.120.1 to 234.225.127.254234.225.127.2552,046
49234.225.128.0/21234.225.128.1 to 234.225.135.254234.225.135.2552,046
50234.225.136.0/21234.225.136.1 to 234.225.143.254234.225.143.2552,046
51234.225.144.0/21234.225.144.1 to 234.225.151.254234.225.151.2552,046
52234.225.152.0/21234.225.152.1 to 234.225.159.254234.225.159.2552,046
53234.225.160.0/21234.225.160.1 to 234.225.167.254234.225.167.2552,046
54234.225.168.0/21234.225.168.1 to 234.225.175.254234.225.175.2552,046
55234.225.176.0/21234.225.176.1 to 234.225.183.254234.225.183.2552,046
56234.225.184.0/21234.225.184.1 to 234.225.191.254234.225.191.2552,046
57234.225.192.0/21234.225.192.1 to 234.225.199.254234.225.199.2552,046
58234.225.200.0/21234.225.200.1 to 234.225.207.254234.225.207.2552,046
59234.225.208.0/21234.225.208.1 to 234.225.215.254234.225.215.2552,046
60234.225.216.0/21234.225.216.1 to 234.225.223.254234.225.223.2552,046
61234.225.224.0/21234.225.224.1 to 234.225.231.254234.225.231.2552,046
62234.225.232.0/21234.225.232.1 to 234.225.239.254234.225.239.2552,046
63234.225.240.0/21234.225.240.1 to 234.225.247.254234.225.247.2552,046
64234.225.248.0/21234.225.248.1 to 234.225.255.254234.225.255.2552,046
65234.226.0.0/21234.226.0.1 to 234.226.7.254234.226.7.2552,046
66234.226.8.0/21234.226.8.1 to 234.226.15.254234.226.15.2552,046
67234.226.16.0/21234.226.16.1 to 234.226.23.254234.226.23.2552,046
68234.226.24.0/21234.226.24.1 to 234.226.31.254234.226.31.2552,046
69234.226.32.0/21234.226.32.1 to 234.226.39.254234.226.39.2552,046
70234.226.40.0/21234.226.40.1 to 234.226.47.254234.226.47.2552,046
71234.226.48.0/21234.226.48.1 to 234.226.55.254234.226.55.2552,046
72234.226.56.0/21234.226.56.1 to 234.226.63.254234.226.63.2552,046
73234.226.64.0/21234.226.64.1 to 234.226.71.254234.226.71.2552,046
74234.226.72.0/21234.226.72.1 to 234.226.79.254234.226.79.2552,046
75234.226.80.0/21234.226.80.1 to 234.226.87.254234.226.87.2552,046
76234.226.88.0/21234.226.88.1 to 234.226.95.254234.226.95.2552,046
77234.226.96.0/21234.226.96.1 to 234.226.103.254234.226.103.2552,046
78234.226.104.0/21234.226.104.1 to 234.226.111.254234.226.111.2552,046
79234.226.112.0/21234.226.112.1 to 234.226.119.254234.226.119.2552,046
80234.226.120.0/21234.226.120.1 to 234.226.127.254234.226.127.2552,046
81234.226.128.0/21234.226.128.1 to 234.226.135.254234.226.135.2552,046
82234.226.136.0/21234.226.136.1 to 234.226.143.254234.226.143.2552,046
83234.226.144.0/21234.226.144.1 to 234.226.151.254234.226.151.2552,046
84234.226.152.0/21234.226.152.1 to 234.226.159.254234.226.159.2552,046
85234.226.160.0/21234.226.160.1 to 234.226.167.254234.226.167.2552,046
86234.226.168.0/21234.226.168.1 to 234.226.175.254234.226.175.2552,046
87234.226.176.0/21234.226.176.1 to 234.226.183.254234.226.183.2552,046
88234.226.184.0/21234.226.184.1 to 234.226.191.254234.226.191.2552,046
89234.226.192.0/21234.226.192.1 to 234.226.199.254234.226.199.2552,046
90234.226.200.0/21234.226.200.1 to 234.226.207.254234.226.207.2552,046
91234.226.208.0/21234.226.208.1 to 234.226.215.254234.226.215.2552,046
92234.226.216.0/21234.226.216.1 to 234.226.223.254234.226.223.2552,046
93234.226.224.0/21234.226.224.1 to 234.226.231.254234.226.231.2552,046
94234.226.232.0/21234.226.232.1 to 234.226.239.254234.226.239.2552,046
95234.226.240.0/21234.226.240.1 to 234.226.247.254234.226.247.2552,046
96234.226.248.0/21234.226.248.1 to 234.226.255.254234.226.255.2552,046
97234.227.0.0/21234.227.0.1 to 234.227.7.254234.227.7.2552,046
98234.227.8.0/21234.227.8.1 to 234.227.15.254234.227.15.2552,046
99234.227.16.0/21234.227.16.1 to 234.227.23.254234.227.23.2552,046
100234.227.24.0/21234.227.24.1 to 234.227.31.254234.227.31.2552,046
101234.227.32.0/21234.227.32.1 to 234.227.39.254234.227.39.2552,046
102234.227.40.0/21234.227.40.1 to 234.227.47.254234.227.47.2552,046
103234.227.48.0/21234.227.48.1 to 234.227.55.254234.227.55.2552,046
104234.227.56.0/21234.227.56.1 to 234.227.63.254234.227.63.2552,046
105234.227.64.0/21234.227.64.1 to 234.227.71.254234.227.71.2552,046
106234.227.72.0/21234.227.72.1 to 234.227.79.254234.227.79.2552,046
107234.227.80.0/21234.227.80.1 to 234.227.87.254234.227.87.2552,046
108234.227.88.0/21234.227.88.1 to 234.227.95.254234.227.95.2552,046
109234.227.96.0/21234.227.96.1 to 234.227.103.254234.227.103.2552,046
110234.227.104.0/21234.227.104.1 to 234.227.111.254234.227.111.2552,046
111234.227.112.0/21234.227.112.1 to 234.227.119.254234.227.119.2552,046
112234.227.120.0/21234.227.120.1 to 234.227.127.254234.227.127.2552,046
113234.227.128.0/21234.227.128.1 to 234.227.135.254234.227.135.2552,046
114234.227.136.0/21234.227.136.1 to 234.227.143.254234.227.143.2552,046
115234.227.144.0/21234.227.144.1 to 234.227.151.254234.227.151.2552,046
116234.227.152.0/21234.227.152.1 to 234.227.159.254234.227.159.2552,046
117234.227.160.0/21234.227.160.1 to 234.227.167.254234.227.167.2552,046
118234.227.168.0/21234.227.168.1 to 234.227.175.254234.227.175.2552,046
119234.227.176.0/21234.227.176.1 to 234.227.183.254234.227.183.2552,046
120234.227.184.0/21234.227.184.1 to 234.227.191.254234.227.191.2552,046
121234.227.192.0/21234.227.192.1 to 234.227.199.254234.227.199.2552,046
122234.227.200.0/21234.227.200.1 to 234.227.207.254234.227.207.2552,046
123234.227.208.0/21234.227.208.1 to 234.227.215.254234.227.215.2552,046
124234.227.216.0/21234.227.216.1 to 234.227.223.254234.227.223.2552,046
125234.227.224.0/21234.227.224.1 to 234.227.231.254234.227.231.2552,046
126234.227.232.0/21234.227.232.1 to 234.227.239.254234.227.239.2552,046
127234.227.240.0/21234.227.240.1 to 234.227.247.254234.227.247.2552,046
128234.227.248.0/21234.227.248.1 to 234.227.255.254234.227.255.2552,046
129234.228.0.0/21234.228.0.1 to 234.228.7.254234.228.7.2552,046
130234.228.8.0/21234.228.8.1 to 234.228.15.254234.228.15.2552,046
131234.228.16.0/21234.228.16.1 to 234.228.23.254234.228.23.2552,046
132234.228.24.0/21234.228.24.1 to 234.228.31.254234.228.31.2552,046
133234.228.32.0/21234.228.32.1 to 234.228.39.254234.228.39.2552,046
134234.228.40.0/21234.228.40.1 to 234.228.47.254234.228.47.2552,046
135234.228.48.0/21234.228.48.1 to 234.228.55.254234.228.55.2552,046
136234.228.56.0/21234.228.56.1 to 234.228.63.254234.228.63.2552,046
137234.228.64.0/21234.228.64.1 to 234.228.71.254234.228.71.2552,046
138234.228.72.0/21234.228.72.1 to 234.228.79.254234.228.79.2552,046
139234.228.80.0/21234.228.80.1 to 234.228.87.254234.228.87.2552,046
140234.228.88.0/21234.228.88.1 to 234.228.95.254234.228.95.2552,046
141234.228.96.0/21234.228.96.1 to 234.228.103.254234.228.103.2552,046
142234.228.104.0/21234.228.104.1 to 234.228.111.254234.228.111.2552,046
143234.228.112.0/21234.228.112.1 to 234.228.119.254234.228.119.2552,046
144234.228.120.0/21234.228.120.1 to 234.228.127.254234.228.127.2552,046
145234.228.128.0/21234.228.128.1 to 234.228.135.254234.228.135.2552,046
146234.228.136.0/21234.228.136.1 to 234.228.143.254234.228.143.2552,046
147234.228.144.0/21234.228.144.1 to 234.228.151.254234.228.151.2552,046
148234.228.152.0/21234.228.152.1 to 234.228.159.254234.228.159.2552,046
149234.228.160.0/21234.228.160.1 to 234.228.167.254234.228.167.2552,046
150234.228.168.0/21234.228.168.1 to 234.228.175.254234.228.175.2552,046
151234.228.176.0/21234.228.176.1 to 234.228.183.254234.228.183.2552,046
152234.228.184.0/21234.228.184.1 to 234.228.191.254234.228.191.2552,046
153234.228.192.0/21234.228.192.1 to 234.228.199.254234.228.199.2552,046
154234.228.200.0/21234.228.200.1 to 234.228.207.254234.228.207.2552,046
155234.228.208.0/21234.228.208.1 to 234.228.215.254234.228.215.2552,046
156234.228.216.0/21234.228.216.1 to 234.228.223.254234.228.223.2552,046
157234.228.224.0/21234.228.224.1 to 234.228.231.254234.228.231.2552,046
158234.228.232.0/21234.228.232.1 to 234.228.239.254234.228.239.2552,046
159234.228.240.0/21234.228.240.1 to 234.228.247.254234.228.247.2552,046
160234.228.248.0/21234.228.248.1 to 234.228.255.254234.228.255.2552,046
161234.229.0.0/21234.229.0.1 to 234.229.7.254234.229.7.2552,046
162234.229.8.0/21234.229.8.1 to 234.229.15.254234.229.15.2552,046
163234.229.16.0/21234.229.16.1 to 234.229.23.254234.229.23.2552,046
164234.229.24.0/21234.229.24.1 to 234.229.31.254234.229.31.2552,046
165234.229.32.0/21234.229.32.1 to 234.229.39.254234.229.39.2552,046
166234.229.40.0/21234.229.40.1 to 234.229.47.254234.229.47.2552,046
167234.229.48.0/21234.229.48.1 to 234.229.55.254234.229.55.2552,046
168234.229.56.0/21234.229.56.1 to 234.229.63.254234.229.63.2552,046
169234.229.64.0/21234.229.64.1 to 234.229.71.254234.229.71.2552,046
170234.229.72.0/21234.229.72.1 to 234.229.79.254234.229.79.2552,046
171234.229.80.0/21234.229.80.1 to 234.229.87.254234.229.87.2552,046
172234.229.88.0/21234.229.88.1 to 234.229.95.254234.229.95.2552,046
173234.229.96.0/21234.229.96.1 to 234.229.103.254234.229.103.2552,046
174234.229.104.0/21234.229.104.1 to 234.229.111.254234.229.111.2552,046
175234.229.112.0/21234.229.112.1 to 234.229.119.254234.229.119.2552,046
176234.229.120.0/21234.229.120.1 to 234.229.127.254234.229.127.2552,046
177234.229.128.0/21234.229.128.1 to 234.229.135.254234.229.135.2552,046
178234.229.136.0/21234.229.136.1 to 234.229.143.254234.229.143.2552,046
179234.229.144.0/21234.229.144.1 to 234.229.151.254234.229.151.2552,046
180234.229.152.0/21234.229.152.1 to 234.229.159.254234.229.159.2552,046
181234.229.160.0/21234.229.160.1 to 234.229.167.254234.229.167.2552,046
182234.229.168.0/21234.229.168.1 to 234.229.175.254234.229.175.2552,046
183234.229.176.0/21234.229.176.1 to 234.229.183.254234.229.183.2552,046
184234.229.184.0/21234.229.184.1 to 234.229.191.254234.229.191.2552,046
185234.229.192.0/21234.229.192.1 to 234.229.199.254234.229.199.2552,046
186234.229.200.0/21234.229.200.1 to 234.229.207.254234.229.207.2552,046
187234.229.208.0/21234.229.208.1 to 234.229.215.254234.229.215.2552,046
188234.229.216.0/21234.229.216.1 to 234.229.223.254234.229.223.2552,046
189234.229.224.0/21234.229.224.1 to 234.229.231.254234.229.231.2552,046
190234.229.232.0/21234.229.232.1 to 234.229.239.254234.229.239.2552,046
191234.229.240.0/21234.229.240.1 to 234.229.247.254234.229.247.2552,046
192234.229.248.0/21234.229.248.1 to 234.229.255.254234.229.255.2552,046
193234.230.0.0/21234.230.0.1 to 234.230.7.254234.230.7.2552,046
194234.230.8.0/21234.230.8.1 to 234.230.15.254234.230.15.2552,046
195234.230.16.0/21234.230.16.1 to 234.230.23.254234.230.23.2552,046
196234.230.24.0/21234.230.24.1 to 234.230.31.254234.230.31.2552,046
197234.230.32.0/21234.230.32.1 to 234.230.39.254234.230.39.2552,046
198234.230.40.0/21234.230.40.1 to 234.230.47.254234.230.47.2552,046
199234.230.48.0/21234.230.48.1 to 234.230.55.254234.230.55.2552,046
200234.230.56.0/21234.230.56.1 to 234.230.63.254234.230.63.2552,046
201234.230.64.0/21234.230.64.1 to 234.230.71.254234.230.71.2552,046
202234.230.72.0/21234.230.72.1 to 234.230.79.254234.230.79.2552,046
203234.230.80.0/21234.230.80.1 to 234.230.87.254234.230.87.2552,046
204234.230.88.0/21234.230.88.1 to 234.230.95.254234.230.95.2552,046
205234.230.96.0/21234.230.96.1 to 234.230.103.254234.230.103.2552,046
206234.230.104.0/21234.230.104.1 to 234.230.111.254234.230.111.2552,046
207234.230.112.0/21234.230.112.1 to 234.230.119.254234.230.119.2552,046
208234.230.120.0/21234.230.120.1 to 234.230.127.254234.230.127.2552,046
209234.230.128.0/21234.230.128.1 to 234.230.135.254234.230.135.2552,046
210234.230.136.0/21234.230.136.1 to 234.230.143.254234.230.143.2552,046
211234.230.144.0/21234.230.144.1 to 234.230.151.254234.230.151.2552,046
212234.230.152.0/21234.230.152.1 to 234.230.159.254234.230.159.2552,046
213234.230.160.0/21234.230.160.1 to 234.230.167.254234.230.167.2552,046
214234.230.168.0/21234.230.168.1 to 234.230.175.254234.230.175.2552,046
215234.230.176.0/21234.230.176.1 to 234.230.183.254234.230.183.2552,046
216234.230.184.0/21234.230.184.1 to 234.230.191.254234.230.191.2552,046
217234.230.192.0/21234.230.192.1 to 234.230.199.254234.230.199.2552,046
218234.230.200.0/21234.230.200.1 to 234.230.207.254234.230.207.2552,046
219234.230.208.0/21234.230.208.1 to 234.230.215.254234.230.215.2552,046
220234.230.216.0/21234.230.216.1 to 234.230.223.254234.230.223.2552,046
221234.230.224.0/21234.230.224.1 to 234.230.231.254234.230.231.2552,046
222234.230.232.0/21234.230.232.1 to 234.230.239.254234.230.239.2552,046
223234.230.240.0/21234.230.240.1 to 234.230.247.254234.230.247.2552,046
224234.230.248.0/21234.230.248.1 to 234.230.255.254234.230.255.2552,046
225234.231.0.0/21234.231.0.1 to 234.231.7.254234.231.7.2552,046
226234.231.8.0/21234.231.8.1 to 234.231.15.254234.231.15.2552,046
227234.231.16.0/21234.231.16.1 to 234.231.23.254234.231.23.2552,046
228234.231.24.0/21234.231.24.1 to 234.231.31.254234.231.31.2552,046
229234.231.32.0/21234.231.32.1 to 234.231.39.254234.231.39.2552,046
230234.231.40.0/21234.231.40.1 to 234.231.47.254234.231.47.2552,046
231234.231.48.0/21234.231.48.1 to 234.231.55.254234.231.55.2552,046
232234.231.56.0/21234.231.56.1 to 234.231.63.254234.231.63.2552,046
233234.231.64.0/21234.231.64.1 to 234.231.71.254234.231.71.2552,046
234234.231.72.0/21234.231.72.1 to 234.231.79.254234.231.79.2552,046
235234.231.80.0/21234.231.80.1 to 234.231.87.254234.231.87.2552,046
236234.231.88.0/21234.231.88.1 to 234.231.95.254234.231.95.2552,046
237234.231.96.0/21234.231.96.1 to 234.231.103.254234.231.103.2552,046
238234.231.104.0/21234.231.104.1 to 234.231.111.254234.231.111.2552,046
239234.231.112.0/21234.231.112.1 to 234.231.119.254234.231.119.2552,046
240234.231.120.0/21234.231.120.1 to 234.231.127.254234.231.127.2552,046
241234.231.128.0/21234.231.128.1 to 234.231.135.254234.231.135.2552,046
242234.231.136.0/21234.231.136.1 to 234.231.143.254234.231.143.2552,046
243234.231.144.0/21234.231.144.1 to 234.231.151.254234.231.151.2552,046
244234.231.152.0/21234.231.152.1 to 234.231.159.254234.231.159.2552,046
245234.231.160.0/21234.231.160.1 to 234.231.167.254234.231.167.2552,046
246234.231.168.0/21234.231.168.1 to 234.231.175.254234.231.175.2552,046
247234.231.176.0/21234.231.176.1 to 234.231.183.254234.231.183.2552,046
248234.231.184.0/21234.231.184.1 to 234.231.191.254234.231.191.2552,046
249234.231.192.0/21234.231.192.1 to 234.231.199.254234.231.199.2552,046
250234.231.200.0/21234.231.200.1 to 234.231.207.254234.231.207.2552,046
251234.231.208.0/21234.231.208.1 to 234.231.215.254234.231.215.2552,046
252234.231.216.0/21234.231.216.1 to 234.231.223.254234.231.223.2552,046
253234.231.224.0/21234.231.224.1 to 234.231.231.254234.231.231.2552,046
254234.231.232.0/21234.231.232.1 to 234.231.239.254234.231.239.2552,046
255234.231.240.0/21234.231.240.1 to 234.231.247.254234.231.247.2552,046
256234.231.248.0/21234.231.248.1 to 234.231.255.254234.231.255.2552,046

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.