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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.

Network176.0.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
176.0.0.0
Broadcast address
176.31.255.255
First usable
176.0.0.1
Last usable
176.31.255.254
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
Public public
Old class
B (default /16)
As numbers
Hex B0000000 · Integer 2952790016 to 2954887167
Reverse DNS zones
0.176.in-addr.arpa
1.176.in-addr.arpa
2.176.in-addr.arpa
3.176.in-addr.arpa
4.176.in-addr.arpa
5.176.in-addr.arpa
6.176.in-addr.arpa
7.176.in-addr.arpa
8.176.in-addr.arpa
9.176.in-addr.arpa
10.176.in-addr.arpa
11.176.in-addr.arpa
12.176.in-addr.arpa
13.176.in-addr.arpa
14.176.in-addr.arpa
15.176.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
Address10110000.00000000.00000000.00000000176.0.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network10110000.00000000.00000000.00000000176.0.0.0
Broadcast10110000.00011111.11111111.11111111176.31.255.255
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)

176.0.0.0/11 makes 1,024 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1176.0.0.0/21176.0.0.1 to 176.0.7.254176.0.7.2552,046
2176.0.8.0/21176.0.8.1 to 176.0.15.254176.0.15.2552,046
3176.0.16.0/21176.0.16.1 to 176.0.23.254176.0.23.2552,046
4176.0.24.0/21176.0.24.1 to 176.0.31.254176.0.31.2552,046
5176.0.32.0/21176.0.32.1 to 176.0.39.254176.0.39.2552,046
6176.0.40.0/21176.0.40.1 to 176.0.47.254176.0.47.2552,046
7176.0.48.0/21176.0.48.1 to 176.0.55.254176.0.55.2552,046
8176.0.56.0/21176.0.56.1 to 176.0.63.254176.0.63.2552,046
9176.0.64.0/21176.0.64.1 to 176.0.71.254176.0.71.2552,046
10176.0.72.0/21176.0.72.1 to 176.0.79.254176.0.79.2552,046
11176.0.80.0/21176.0.80.1 to 176.0.87.254176.0.87.2552,046
12176.0.88.0/21176.0.88.1 to 176.0.95.254176.0.95.2552,046
13176.0.96.0/21176.0.96.1 to 176.0.103.254176.0.103.2552,046
14176.0.104.0/21176.0.104.1 to 176.0.111.254176.0.111.2552,046
15176.0.112.0/21176.0.112.1 to 176.0.119.254176.0.119.2552,046
16176.0.120.0/21176.0.120.1 to 176.0.127.254176.0.127.2552,046
17176.0.128.0/21176.0.128.1 to 176.0.135.254176.0.135.2552,046
18176.0.136.0/21176.0.136.1 to 176.0.143.254176.0.143.2552,046
19176.0.144.0/21176.0.144.1 to 176.0.151.254176.0.151.2552,046
20176.0.152.0/21176.0.152.1 to 176.0.159.254176.0.159.2552,046
21176.0.160.0/21176.0.160.1 to 176.0.167.254176.0.167.2552,046
22176.0.168.0/21176.0.168.1 to 176.0.175.254176.0.175.2552,046
23176.0.176.0/21176.0.176.1 to 176.0.183.254176.0.183.2552,046
24176.0.184.0/21176.0.184.1 to 176.0.191.254176.0.191.2552,046
25176.0.192.0/21176.0.192.1 to 176.0.199.254176.0.199.2552,046
26176.0.200.0/21176.0.200.1 to 176.0.207.254176.0.207.2552,046
27176.0.208.0/21176.0.208.1 to 176.0.215.254176.0.215.2552,046
28176.0.216.0/21176.0.216.1 to 176.0.223.254176.0.223.2552,046
29176.0.224.0/21176.0.224.1 to 176.0.231.254176.0.231.2552,046
30176.0.232.0/21176.0.232.1 to 176.0.239.254176.0.239.2552,046
31176.0.240.0/21176.0.240.1 to 176.0.247.254176.0.247.2552,046
32176.0.248.0/21176.0.248.1 to 176.0.255.254176.0.255.2552,046
33176.1.0.0/21176.1.0.1 to 176.1.7.254176.1.7.2552,046
34176.1.8.0/21176.1.8.1 to 176.1.15.254176.1.15.2552,046
35176.1.16.0/21176.1.16.1 to 176.1.23.254176.1.23.2552,046
36176.1.24.0/21176.1.24.1 to 176.1.31.254176.1.31.2552,046
37176.1.32.0/21176.1.32.1 to 176.1.39.254176.1.39.2552,046
38176.1.40.0/21176.1.40.1 to 176.1.47.254176.1.47.2552,046
39176.1.48.0/21176.1.48.1 to 176.1.55.254176.1.55.2552,046
40176.1.56.0/21176.1.56.1 to 176.1.63.254176.1.63.2552,046
41176.1.64.0/21176.1.64.1 to 176.1.71.254176.1.71.2552,046
42176.1.72.0/21176.1.72.1 to 176.1.79.254176.1.79.2552,046
43176.1.80.0/21176.1.80.1 to 176.1.87.254176.1.87.2552,046
44176.1.88.0/21176.1.88.1 to 176.1.95.254176.1.95.2552,046
45176.1.96.0/21176.1.96.1 to 176.1.103.254176.1.103.2552,046
46176.1.104.0/21176.1.104.1 to 176.1.111.254176.1.111.2552,046
47176.1.112.0/21176.1.112.1 to 176.1.119.254176.1.119.2552,046
48176.1.120.0/21176.1.120.1 to 176.1.127.254176.1.127.2552,046
49176.1.128.0/21176.1.128.1 to 176.1.135.254176.1.135.2552,046
50176.1.136.0/21176.1.136.1 to 176.1.143.254176.1.143.2552,046
51176.1.144.0/21176.1.144.1 to 176.1.151.254176.1.151.2552,046
52176.1.152.0/21176.1.152.1 to 176.1.159.254176.1.159.2552,046
53176.1.160.0/21176.1.160.1 to 176.1.167.254176.1.167.2552,046
54176.1.168.0/21176.1.168.1 to 176.1.175.254176.1.175.2552,046
55176.1.176.0/21176.1.176.1 to 176.1.183.254176.1.183.2552,046
56176.1.184.0/21176.1.184.1 to 176.1.191.254176.1.191.2552,046
57176.1.192.0/21176.1.192.1 to 176.1.199.254176.1.199.2552,046
58176.1.200.0/21176.1.200.1 to 176.1.207.254176.1.207.2552,046
59176.1.208.0/21176.1.208.1 to 176.1.215.254176.1.215.2552,046
60176.1.216.0/21176.1.216.1 to 176.1.223.254176.1.223.2552,046
61176.1.224.0/21176.1.224.1 to 176.1.231.254176.1.231.2552,046
62176.1.232.0/21176.1.232.1 to 176.1.239.254176.1.239.2552,046
63176.1.240.0/21176.1.240.1 to 176.1.247.254176.1.247.2552,046
64176.1.248.0/21176.1.248.1 to 176.1.255.254176.1.255.2552,046
65176.2.0.0/21176.2.0.1 to 176.2.7.254176.2.7.2552,046
66176.2.8.0/21176.2.8.1 to 176.2.15.254176.2.15.2552,046
67176.2.16.0/21176.2.16.1 to 176.2.23.254176.2.23.2552,046
68176.2.24.0/21176.2.24.1 to 176.2.31.254176.2.31.2552,046
69176.2.32.0/21176.2.32.1 to 176.2.39.254176.2.39.2552,046
70176.2.40.0/21176.2.40.1 to 176.2.47.254176.2.47.2552,046
71176.2.48.0/21176.2.48.1 to 176.2.55.254176.2.55.2552,046
72176.2.56.0/21176.2.56.1 to 176.2.63.254176.2.63.2552,046
73176.2.64.0/21176.2.64.1 to 176.2.71.254176.2.71.2552,046
74176.2.72.0/21176.2.72.1 to 176.2.79.254176.2.79.2552,046
75176.2.80.0/21176.2.80.1 to 176.2.87.254176.2.87.2552,046
76176.2.88.0/21176.2.88.1 to 176.2.95.254176.2.95.2552,046
77176.2.96.0/21176.2.96.1 to 176.2.103.254176.2.103.2552,046
78176.2.104.0/21176.2.104.1 to 176.2.111.254176.2.111.2552,046
79176.2.112.0/21176.2.112.1 to 176.2.119.254176.2.119.2552,046
80176.2.120.0/21176.2.120.1 to 176.2.127.254176.2.127.2552,046
81176.2.128.0/21176.2.128.1 to 176.2.135.254176.2.135.2552,046
82176.2.136.0/21176.2.136.1 to 176.2.143.254176.2.143.2552,046
83176.2.144.0/21176.2.144.1 to 176.2.151.254176.2.151.2552,046
84176.2.152.0/21176.2.152.1 to 176.2.159.254176.2.159.2552,046
85176.2.160.0/21176.2.160.1 to 176.2.167.254176.2.167.2552,046
86176.2.168.0/21176.2.168.1 to 176.2.175.254176.2.175.2552,046
87176.2.176.0/21176.2.176.1 to 176.2.183.254176.2.183.2552,046
88176.2.184.0/21176.2.184.1 to 176.2.191.254176.2.191.2552,046
89176.2.192.0/21176.2.192.1 to 176.2.199.254176.2.199.2552,046
90176.2.200.0/21176.2.200.1 to 176.2.207.254176.2.207.2552,046
91176.2.208.0/21176.2.208.1 to 176.2.215.254176.2.215.2552,046
92176.2.216.0/21176.2.216.1 to 176.2.223.254176.2.223.2552,046
93176.2.224.0/21176.2.224.1 to 176.2.231.254176.2.231.2552,046
94176.2.232.0/21176.2.232.1 to 176.2.239.254176.2.239.2552,046
95176.2.240.0/21176.2.240.1 to 176.2.247.254176.2.247.2552,046
96176.2.248.0/21176.2.248.1 to 176.2.255.254176.2.255.2552,046
97176.3.0.0/21176.3.0.1 to 176.3.7.254176.3.7.2552,046
98176.3.8.0/21176.3.8.1 to 176.3.15.254176.3.15.2552,046
99176.3.16.0/21176.3.16.1 to 176.3.23.254176.3.23.2552,046
100176.3.24.0/21176.3.24.1 to 176.3.31.254176.3.31.2552,046
101176.3.32.0/21176.3.32.1 to 176.3.39.254176.3.39.2552,046
102176.3.40.0/21176.3.40.1 to 176.3.47.254176.3.47.2552,046
103176.3.48.0/21176.3.48.1 to 176.3.55.254176.3.55.2552,046
104176.3.56.0/21176.3.56.1 to 176.3.63.254176.3.63.2552,046
105176.3.64.0/21176.3.64.1 to 176.3.71.254176.3.71.2552,046
106176.3.72.0/21176.3.72.1 to 176.3.79.254176.3.79.2552,046
107176.3.80.0/21176.3.80.1 to 176.3.87.254176.3.87.2552,046
108176.3.88.0/21176.3.88.1 to 176.3.95.254176.3.95.2552,046
109176.3.96.0/21176.3.96.1 to 176.3.103.254176.3.103.2552,046
110176.3.104.0/21176.3.104.1 to 176.3.111.254176.3.111.2552,046
111176.3.112.0/21176.3.112.1 to 176.3.119.254176.3.119.2552,046
112176.3.120.0/21176.3.120.1 to 176.3.127.254176.3.127.2552,046
113176.3.128.0/21176.3.128.1 to 176.3.135.254176.3.135.2552,046
114176.3.136.0/21176.3.136.1 to 176.3.143.254176.3.143.2552,046
115176.3.144.0/21176.3.144.1 to 176.3.151.254176.3.151.2552,046
116176.3.152.0/21176.3.152.1 to 176.3.159.254176.3.159.2552,046
117176.3.160.0/21176.3.160.1 to 176.3.167.254176.3.167.2552,046
118176.3.168.0/21176.3.168.1 to 176.3.175.254176.3.175.2552,046
119176.3.176.0/21176.3.176.1 to 176.3.183.254176.3.183.2552,046
120176.3.184.0/21176.3.184.1 to 176.3.191.254176.3.191.2552,046
121176.3.192.0/21176.3.192.1 to 176.3.199.254176.3.199.2552,046
122176.3.200.0/21176.3.200.1 to 176.3.207.254176.3.207.2552,046
123176.3.208.0/21176.3.208.1 to 176.3.215.254176.3.215.2552,046
124176.3.216.0/21176.3.216.1 to 176.3.223.254176.3.223.2552,046
125176.3.224.0/21176.3.224.1 to 176.3.231.254176.3.231.2552,046
126176.3.232.0/21176.3.232.1 to 176.3.239.254176.3.239.2552,046
127176.3.240.0/21176.3.240.1 to 176.3.247.254176.3.247.2552,046
128176.3.248.0/21176.3.248.1 to 176.3.255.254176.3.255.2552,046
129176.4.0.0/21176.4.0.1 to 176.4.7.254176.4.7.2552,046
130176.4.8.0/21176.4.8.1 to 176.4.15.254176.4.15.2552,046
131176.4.16.0/21176.4.16.1 to 176.4.23.254176.4.23.2552,046
132176.4.24.0/21176.4.24.1 to 176.4.31.254176.4.31.2552,046
133176.4.32.0/21176.4.32.1 to 176.4.39.254176.4.39.2552,046
134176.4.40.0/21176.4.40.1 to 176.4.47.254176.4.47.2552,046
135176.4.48.0/21176.4.48.1 to 176.4.55.254176.4.55.2552,046
136176.4.56.0/21176.4.56.1 to 176.4.63.254176.4.63.2552,046
137176.4.64.0/21176.4.64.1 to 176.4.71.254176.4.71.2552,046
138176.4.72.0/21176.4.72.1 to 176.4.79.254176.4.79.2552,046
139176.4.80.0/21176.4.80.1 to 176.4.87.254176.4.87.2552,046
140176.4.88.0/21176.4.88.1 to 176.4.95.254176.4.95.2552,046
141176.4.96.0/21176.4.96.1 to 176.4.103.254176.4.103.2552,046
142176.4.104.0/21176.4.104.1 to 176.4.111.254176.4.111.2552,046
143176.4.112.0/21176.4.112.1 to 176.4.119.254176.4.119.2552,046
144176.4.120.0/21176.4.120.1 to 176.4.127.254176.4.127.2552,046
145176.4.128.0/21176.4.128.1 to 176.4.135.254176.4.135.2552,046
146176.4.136.0/21176.4.136.1 to 176.4.143.254176.4.143.2552,046
147176.4.144.0/21176.4.144.1 to 176.4.151.254176.4.151.2552,046
148176.4.152.0/21176.4.152.1 to 176.4.159.254176.4.159.2552,046
149176.4.160.0/21176.4.160.1 to 176.4.167.254176.4.167.2552,046
150176.4.168.0/21176.4.168.1 to 176.4.175.254176.4.175.2552,046
151176.4.176.0/21176.4.176.1 to 176.4.183.254176.4.183.2552,046
152176.4.184.0/21176.4.184.1 to 176.4.191.254176.4.191.2552,046
153176.4.192.0/21176.4.192.1 to 176.4.199.254176.4.199.2552,046
154176.4.200.0/21176.4.200.1 to 176.4.207.254176.4.207.2552,046
155176.4.208.0/21176.4.208.1 to 176.4.215.254176.4.215.2552,046
156176.4.216.0/21176.4.216.1 to 176.4.223.254176.4.223.2552,046
157176.4.224.0/21176.4.224.1 to 176.4.231.254176.4.231.2552,046
158176.4.232.0/21176.4.232.1 to 176.4.239.254176.4.239.2552,046
159176.4.240.0/21176.4.240.1 to 176.4.247.254176.4.247.2552,046
160176.4.248.0/21176.4.248.1 to 176.4.255.254176.4.255.2552,046
161176.5.0.0/21176.5.0.1 to 176.5.7.254176.5.7.2552,046
162176.5.8.0/21176.5.8.1 to 176.5.15.254176.5.15.2552,046
163176.5.16.0/21176.5.16.1 to 176.5.23.254176.5.23.2552,046
164176.5.24.0/21176.5.24.1 to 176.5.31.254176.5.31.2552,046
165176.5.32.0/21176.5.32.1 to 176.5.39.254176.5.39.2552,046
166176.5.40.0/21176.5.40.1 to 176.5.47.254176.5.47.2552,046
167176.5.48.0/21176.5.48.1 to 176.5.55.254176.5.55.2552,046
168176.5.56.0/21176.5.56.1 to 176.5.63.254176.5.63.2552,046
169176.5.64.0/21176.5.64.1 to 176.5.71.254176.5.71.2552,046
170176.5.72.0/21176.5.72.1 to 176.5.79.254176.5.79.2552,046
171176.5.80.0/21176.5.80.1 to 176.5.87.254176.5.87.2552,046
172176.5.88.0/21176.5.88.1 to 176.5.95.254176.5.95.2552,046
173176.5.96.0/21176.5.96.1 to 176.5.103.254176.5.103.2552,046
174176.5.104.0/21176.5.104.1 to 176.5.111.254176.5.111.2552,046
175176.5.112.0/21176.5.112.1 to 176.5.119.254176.5.119.2552,046
176176.5.120.0/21176.5.120.1 to 176.5.127.254176.5.127.2552,046
177176.5.128.0/21176.5.128.1 to 176.5.135.254176.5.135.2552,046
178176.5.136.0/21176.5.136.1 to 176.5.143.254176.5.143.2552,046
179176.5.144.0/21176.5.144.1 to 176.5.151.254176.5.151.2552,046
180176.5.152.0/21176.5.152.1 to 176.5.159.254176.5.159.2552,046
181176.5.160.0/21176.5.160.1 to 176.5.167.254176.5.167.2552,046
182176.5.168.0/21176.5.168.1 to 176.5.175.254176.5.175.2552,046
183176.5.176.0/21176.5.176.1 to 176.5.183.254176.5.183.2552,046
184176.5.184.0/21176.5.184.1 to 176.5.191.254176.5.191.2552,046
185176.5.192.0/21176.5.192.1 to 176.5.199.254176.5.199.2552,046
186176.5.200.0/21176.5.200.1 to 176.5.207.254176.5.207.2552,046
187176.5.208.0/21176.5.208.1 to 176.5.215.254176.5.215.2552,046
188176.5.216.0/21176.5.216.1 to 176.5.223.254176.5.223.2552,046
189176.5.224.0/21176.5.224.1 to 176.5.231.254176.5.231.2552,046
190176.5.232.0/21176.5.232.1 to 176.5.239.254176.5.239.2552,046
191176.5.240.0/21176.5.240.1 to 176.5.247.254176.5.247.2552,046
192176.5.248.0/21176.5.248.1 to 176.5.255.254176.5.255.2552,046
193176.6.0.0/21176.6.0.1 to 176.6.7.254176.6.7.2552,046
194176.6.8.0/21176.6.8.1 to 176.6.15.254176.6.15.2552,046
195176.6.16.0/21176.6.16.1 to 176.6.23.254176.6.23.2552,046
196176.6.24.0/21176.6.24.1 to 176.6.31.254176.6.31.2552,046
197176.6.32.0/21176.6.32.1 to 176.6.39.254176.6.39.2552,046
198176.6.40.0/21176.6.40.1 to 176.6.47.254176.6.47.2552,046
199176.6.48.0/21176.6.48.1 to 176.6.55.254176.6.55.2552,046
200176.6.56.0/21176.6.56.1 to 176.6.63.254176.6.63.2552,046
201176.6.64.0/21176.6.64.1 to 176.6.71.254176.6.71.2552,046
202176.6.72.0/21176.6.72.1 to 176.6.79.254176.6.79.2552,046
203176.6.80.0/21176.6.80.1 to 176.6.87.254176.6.87.2552,046
204176.6.88.0/21176.6.88.1 to 176.6.95.254176.6.95.2552,046
205176.6.96.0/21176.6.96.1 to 176.6.103.254176.6.103.2552,046
206176.6.104.0/21176.6.104.1 to 176.6.111.254176.6.111.2552,046
207176.6.112.0/21176.6.112.1 to 176.6.119.254176.6.119.2552,046
208176.6.120.0/21176.6.120.1 to 176.6.127.254176.6.127.2552,046
209176.6.128.0/21176.6.128.1 to 176.6.135.254176.6.135.2552,046
210176.6.136.0/21176.6.136.1 to 176.6.143.254176.6.143.2552,046
211176.6.144.0/21176.6.144.1 to 176.6.151.254176.6.151.2552,046
212176.6.152.0/21176.6.152.1 to 176.6.159.254176.6.159.2552,046
213176.6.160.0/21176.6.160.1 to 176.6.167.254176.6.167.2552,046
214176.6.168.0/21176.6.168.1 to 176.6.175.254176.6.175.2552,046
215176.6.176.0/21176.6.176.1 to 176.6.183.254176.6.183.2552,046
216176.6.184.0/21176.6.184.1 to 176.6.191.254176.6.191.2552,046
217176.6.192.0/21176.6.192.1 to 176.6.199.254176.6.199.2552,046
218176.6.200.0/21176.6.200.1 to 176.6.207.254176.6.207.2552,046
219176.6.208.0/21176.6.208.1 to 176.6.215.254176.6.215.2552,046
220176.6.216.0/21176.6.216.1 to 176.6.223.254176.6.223.2552,046
221176.6.224.0/21176.6.224.1 to 176.6.231.254176.6.231.2552,046
222176.6.232.0/21176.6.232.1 to 176.6.239.254176.6.239.2552,046
223176.6.240.0/21176.6.240.1 to 176.6.247.254176.6.247.2552,046
224176.6.248.0/21176.6.248.1 to 176.6.255.254176.6.255.2552,046
225176.7.0.0/21176.7.0.1 to 176.7.7.254176.7.7.2552,046
226176.7.8.0/21176.7.8.1 to 176.7.15.254176.7.15.2552,046
227176.7.16.0/21176.7.16.1 to 176.7.23.254176.7.23.2552,046
228176.7.24.0/21176.7.24.1 to 176.7.31.254176.7.31.2552,046
229176.7.32.0/21176.7.32.1 to 176.7.39.254176.7.39.2552,046
230176.7.40.0/21176.7.40.1 to 176.7.47.254176.7.47.2552,046
231176.7.48.0/21176.7.48.1 to 176.7.55.254176.7.55.2552,046
232176.7.56.0/21176.7.56.1 to 176.7.63.254176.7.63.2552,046
233176.7.64.0/21176.7.64.1 to 176.7.71.254176.7.71.2552,046
234176.7.72.0/21176.7.72.1 to 176.7.79.254176.7.79.2552,046
235176.7.80.0/21176.7.80.1 to 176.7.87.254176.7.87.2552,046
236176.7.88.0/21176.7.88.1 to 176.7.95.254176.7.95.2552,046
237176.7.96.0/21176.7.96.1 to 176.7.103.254176.7.103.2552,046
238176.7.104.0/21176.7.104.1 to 176.7.111.254176.7.111.2552,046
239176.7.112.0/21176.7.112.1 to 176.7.119.254176.7.119.2552,046
240176.7.120.0/21176.7.120.1 to 176.7.127.254176.7.127.2552,046
241176.7.128.0/21176.7.128.1 to 176.7.135.254176.7.135.2552,046
242176.7.136.0/21176.7.136.1 to 176.7.143.254176.7.143.2552,046
243176.7.144.0/21176.7.144.1 to 176.7.151.254176.7.151.2552,046
244176.7.152.0/21176.7.152.1 to 176.7.159.254176.7.159.2552,046
245176.7.160.0/21176.7.160.1 to 176.7.167.254176.7.167.2552,046
246176.7.168.0/21176.7.168.1 to 176.7.175.254176.7.175.2552,046
247176.7.176.0/21176.7.176.1 to 176.7.183.254176.7.183.2552,046
248176.7.184.0/21176.7.184.1 to 176.7.191.254176.7.191.2552,046
249176.7.192.0/21176.7.192.1 to 176.7.199.254176.7.199.2552,046
250176.7.200.0/21176.7.200.1 to 176.7.207.254176.7.207.2552,046
251176.7.208.0/21176.7.208.1 to 176.7.215.254176.7.215.2552,046
252176.7.216.0/21176.7.216.1 to 176.7.223.254176.7.223.2552,046
253176.7.224.0/21176.7.224.1 to 176.7.231.254176.7.231.2552,046
254176.7.232.0/21176.7.232.1 to 176.7.239.254176.7.239.2552,046
255176.7.240.0/21176.7.240.1 to 176.7.247.254176.7.247.2552,046
256176.7.248.0/21176.7.248.1 to 176.7.255.254176.7.255.2552,046

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.