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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/20
/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 512 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1176.0.0.0/20176.0.0.1 to 176.0.15.254176.0.15.2554,094
2176.0.16.0/20176.0.16.1 to 176.0.31.254176.0.31.2554,094
3176.0.32.0/20176.0.32.1 to 176.0.47.254176.0.47.2554,094
4176.0.48.0/20176.0.48.1 to 176.0.63.254176.0.63.2554,094
5176.0.64.0/20176.0.64.1 to 176.0.79.254176.0.79.2554,094
6176.0.80.0/20176.0.80.1 to 176.0.95.254176.0.95.2554,094
7176.0.96.0/20176.0.96.1 to 176.0.111.254176.0.111.2554,094
8176.0.112.0/20176.0.112.1 to 176.0.127.254176.0.127.2554,094
9176.0.128.0/20176.0.128.1 to 176.0.143.254176.0.143.2554,094
10176.0.144.0/20176.0.144.1 to 176.0.159.254176.0.159.2554,094
11176.0.160.0/20176.0.160.1 to 176.0.175.254176.0.175.2554,094
12176.0.176.0/20176.0.176.1 to 176.0.191.254176.0.191.2554,094
13176.0.192.0/20176.0.192.1 to 176.0.207.254176.0.207.2554,094
14176.0.208.0/20176.0.208.1 to 176.0.223.254176.0.223.2554,094
15176.0.224.0/20176.0.224.1 to 176.0.239.254176.0.239.2554,094
16176.0.240.0/20176.0.240.1 to 176.0.255.254176.0.255.2554,094
17176.1.0.0/20176.1.0.1 to 176.1.15.254176.1.15.2554,094
18176.1.16.0/20176.1.16.1 to 176.1.31.254176.1.31.2554,094
19176.1.32.0/20176.1.32.1 to 176.1.47.254176.1.47.2554,094
20176.1.48.0/20176.1.48.1 to 176.1.63.254176.1.63.2554,094
21176.1.64.0/20176.1.64.1 to 176.1.79.254176.1.79.2554,094
22176.1.80.0/20176.1.80.1 to 176.1.95.254176.1.95.2554,094
23176.1.96.0/20176.1.96.1 to 176.1.111.254176.1.111.2554,094
24176.1.112.0/20176.1.112.1 to 176.1.127.254176.1.127.2554,094
25176.1.128.0/20176.1.128.1 to 176.1.143.254176.1.143.2554,094
26176.1.144.0/20176.1.144.1 to 176.1.159.254176.1.159.2554,094
27176.1.160.0/20176.1.160.1 to 176.1.175.254176.1.175.2554,094
28176.1.176.0/20176.1.176.1 to 176.1.191.254176.1.191.2554,094
29176.1.192.0/20176.1.192.1 to 176.1.207.254176.1.207.2554,094
30176.1.208.0/20176.1.208.1 to 176.1.223.254176.1.223.2554,094
31176.1.224.0/20176.1.224.1 to 176.1.239.254176.1.239.2554,094
32176.1.240.0/20176.1.240.1 to 176.1.255.254176.1.255.2554,094
33176.2.0.0/20176.2.0.1 to 176.2.15.254176.2.15.2554,094
34176.2.16.0/20176.2.16.1 to 176.2.31.254176.2.31.2554,094
35176.2.32.0/20176.2.32.1 to 176.2.47.254176.2.47.2554,094
36176.2.48.0/20176.2.48.1 to 176.2.63.254176.2.63.2554,094
37176.2.64.0/20176.2.64.1 to 176.2.79.254176.2.79.2554,094
38176.2.80.0/20176.2.80.1 to 176.2.95.254176.2.95.2554,094
39176.2.96.0/20176.2.96.1 to 176.2.111.254176.2.111.2554,094
40176.2.112.0/20176.2.112.1 to 176.2.127.254176.2.127.2554,094
41176.2.128.0/20176.2.128.1 to 176.2.143.254176.2.143.2554,094
42176.2.144.0/20176.2.144.1 to 176.2.159.254176.2.159.2554,094
43176.2.160.0/20176.2.160.1 to 176.2.175.254176.2.175.2554,094
44176.2.176.0/20176.2.176.1 to 176.2.191.254176.2.191.2554,094
45176.2.192.0/20176.2.192.1 to 176.2.207.254176.2.207.2554,094
46176.2.208.0/20176.2.208.1 to 176.2.223.254176.2.223.2554,094
47176.2.224.0/20176.2.224.1 to 176.2.239.254176.2.239.2554,094
48176.2.240.0/20176.2.240.1 to 176.2.255.254176.2.255.2554,094
49176.3.0.0/20176.3.0.1 to 176.3.15.254176.3.15.2554,094
50176.3.16.0/20176.3.16.1 to 176.3.31.254176.3.31.2554,094
51176.3.32.0/20176.3.32.1 to 176.3.47.254176.3.47.2554,094
52176.3.48.0/20176.3.48.1 to 176.3.63.254176.3.63.2554,094
53176.3.64.0/20176.3.64.1 to 176.3.79.254176.3.79.2554,094
54176.3.80.0/20176.3.80.1 to 176.3.95.254176.3.95.2554,094
55176.3.96.0/20176.3.96.1 to 176.3.111.254176.3.111.2554,094
56176.3.112.0/20176.3.112.1 to 176.3.127.254176.3.127.2554,094
57176.3.128.0/20176.3.128.1 to 176.3.143.254176.3.143.2554,094
58176.3.144.0/20176.3.144.1 to 176.3.159.254176.3.159.2554,094
59176.3.160.0/20176.3.160.1 to 176.3.175.254176.3.175.2554,094
60176.3.176.0/20176.3.176.1 to 176.3.191.254176.3.191.2554,094
61176.3.192.0/20176.3.192.1 to 176.3.207.254176.3.207.2554,094
62176.3.208.0/20176.3.208.1 to 176.3.223.254176.3.223.2554,094
63176.3.224.0/20176.3.224.1 to 176.3.239.254176.3.239.2554,094
64176.3.240.0/20176.3.240.1 to 176.3.255.254176.3.255.2554,094
65176.4.0.0/20176.4.0.1 to 176.4.15.254176.4.15.2554,094
66176.4.16.0/20176.4.16.1 to 176.4.31.254176.4.31.2554,094
67176.4.32.0/20176.4.32.1 to 176.4.47.254176.4.47.2554,094
68176.4.48.0/20176.4.48.1 to 176.4.63.254176.4.63.2554,094
69176.4.64.0/20176.4.64.1 to 176.4.79.254176.4.79.2554,094
70176.4.80.0/20176.4.80.1 to 176.4.95.254176.4.95.2554,094
71176.4.96.0/20176.4.96.1 to 176.4.111.254176.4.111.2554,094
72176.4.112.0/20176.4.112.1 to 176.4.127.254176.4.127.2554,094
73176.4.128.0/20176.4.128.1 to 176.4.143.254176.4.143.2554,094
74176.4.144.0/20176.4.144.1 to 176.4.159.254176.4.159.2554,094
75176.4.160.0/20176.4.160.1 to 176.4.175.254176.4.175.2554,094
76176.4.176.0/20176.4.176.1 to 176.4.191.254176.4.191.2554,094
77176.4.192.0/20176.4.192.1 to 176.4.207.254176.4.207.2554,094
78176.4.208.0/20176.4.208.1 to 176.4.223.254176.4.223.2554,094
79176.4.224.0/20176.4.224.1 to 176.4.239.254176.4.239.2554,094
80176.4.240.0/20176.4.240.1 to 176.4.255.254176.4.255.2554,094
81176.5.0.0/20176.5.0.1 to 176.5.15.254176.5.15.2554,094
82176.5.16.0/20176.5.16.1 to 176.5.31.254176.5.31.2554,094
83176.5.32.0/20176.5.32.1 to 176.5.47.254176.5.47.2554,094
84176.5.48.0/20176.5.48.1 to 176.5.63.254176.5.63.2554,094
85176.5.64.0/20176.5.64.1 to 176.5.79.254176.5.79.2554,094
86176.5.80.0/20176.5.80.1 to 176.5.95.254176.5.95.2554,094
87176.5.96.0/20176.5.96.1 to 176.5.111.254176.5.111.2554,094
88176.5.112.0/20176.5.112.1 to 176.5.127.254176.5.127.2554,094
89176.5.128.0/20176.5.128.1 to 176.5.143.254176.5.143.2554,094
90176.5.144.0/20176.5.144.1 to 176.5.159.254176.5.159.2554,094
91176.5.160.0/20176.5.160.1 to 176.5.175.254176.5.175.2554,094
92176.5.176.0/20176.5.176.1 to 176.5.191.254176.5.191.2554,094
93176.5.192.0/20176.5.192.1 to 176.5.207.254176.5.207.2554,094
94176.5.208.0/20176.5.208.1 to 176.5.223.254176.5.223.2554,094
95176.5.224.0/20176.5.224.1 to 176.5.239.254176.5.239.2554,094
96176.5.240.0/20176.5.240.1 to 176.5.255.254176.5.255.2554,094
97176.6.0.0/20176.6.0.1 to 176.6.15.254176.6.15.2554,094
98176.6.16.0/20176.6.16.1 to 176.6.31.254176.6.31.2554,094
99176.6.32.0/20176.6.32.1 to 176.6.47.254176.6.47.2554,094
100176.6.48.0/20176.6.48.1 to 176.6.63.254176.6.63.2554,094
101176.6.64.0/20176.6.64.1 to 176.6.79.254176.6.79.2554,094
102176.6.80.0/20176.6.80.1 to 176.6.95.254176.6.95.2554,094
103176.6.96.0/20176.6.96.1 to 176.6.111.254176.6.111.2554,094
104176.6.112.0/20176.6.112.1 to 176.6.127.254176.6.127.2554,094
105176.6.128.0/20176.6.128.1 to 176.6.143.254176.6.143.2554,094
106176.6.144.0/20176.6.144.1 to 176.6.159.254176.6.159.2554,094
107176.6.160.0/20176.6.160.1 to 176.6.175.254176.6.175.2554,094
108176.6.176.0/20176.6.176.1 to 176.6.191.254176.6.191.2554,094
109176.6.192.0/20176.6.192.1 to 176.6.207.254176.6.207.2554,094
110176.6.208.0/20176.6.208.1 to 176.6.223.254176.6.223.2554,094
111176.6.224.0/20176.6.224.1 to 176.6.239.254176.6.239.2554,094
112176.6.240.0/20176.6.240.1 to 176.6.255.254176.6.255.2554,094
113176.7.0.0/20176.7.0.1 to 176.7.15.254176.7.15.2554,094
114176.7.16.0/20176.7.16.1 to 176.7.31.254176.7.31.2554,094
115176.7.32.0/20176.7.32.1 to 176.7.47.254176.7.47.2554,094
116176.7.48.0/20176.7.48.1 to 176.7.63.254176.7.63.2554,094
117176.7.64.0/20176.7.64.1 to 176.7.79.254176.7.79.2554,094
118176.7.80.0/20176.7.80.1 to 176.7.95.254176.7.95.2554,094
119176.7.96.0/20176.7.96.1 to 176.7.111.254176.7.111.2554,094
120176.7.112.0/20176.7.112.1 to 176.7.127.254176.7.127.2554,094
121176.7.128.0/20176.7.128.1 to 176.7.143.254176.7.143.2554,094
122176.7.144.0/20176.7.144.1 to 176.7.159.254176.7.159.2554,094
123176.7.160.0/20176.7.160.1 to 176.7.175.254176.7.175.2554,094
124176.7.176.0/20176.7.176.1 to 176.7.191.254176.7.191.2554,094
125176.7.192.0/20176.7.192.1 to 176.7.207.254176.7.207.2554,094
126176.7.208.0/20176.7.208.1 to 176.7.223.254176.7.223.2554,094
127176.7.224.0/20176.7.224.1 to 176.7.239.254176.7.239.2554,094
128176.7.240.0/20176.7.240.1 to 176.7.255.254176.7.255.2554,094
129176.8.0.0/20176.8.0.1 to 176.8.15.254176.8.15.2554,094
130176.8.16.0/20176.8.16.1 to 176.8.31.254176.8.31.2554,094
131176.8.32.0/20176.8.32.1 to 176.8.47.254176.8.47.2554,094
132176.8.48.0/20176.8.48.1 to 176.8.63.254176.8.63.2554,094
133176.8.64.0/20176.8.64.1 to 176.8.79.254176.8.79.2554,094
134176.8.80.0/20176.8.80.1 to 176.8.95.254176.8.95.2554,094
135176.8.96.0/20176.8.96.1 to 176.8.111.254176.8.111.2554,094
136176.8.112.0/20176.8.112.1 to 176.8.127.254176.8.127.2554,094
137176.8.128.0/20176.8.128.1 to 176.8.143.254176.8.143.2554,094
138176.8.144.0/20176.8.144.1 to 176.8.159.254176.8.159.2554,094
139176.8.160.0/20176.8.160.1 to 176.8.175.254176.8.175.2554,094
140176.8.176.0/20176.8.176.1 to 176.8.191.254176.8.191.2554,094
141176.8.192.0/20176.8.192.1 to 176.8.207.254176.8.207.2554,094
142176.8.208.0/20176.8.208.1 to 176.8.223.254176.8.223.2554,094
143176.8.224.0/20176.8.224.1 to 176.8.239.254176.8.239.2554,094
144176.8.240.0/20176.8.240.1 to 176.8.255.254176.8.255.2554,094
145176.9.0.0/20176.9.0.1 to 176.9.15.254176.9.15.2554,094
146176.9.16.0/20176.9.16.1 to 176.9.31.254176.9.31.2554,094
147176.9.32.0/20176.9.32.1 to 176.9.47.254176.9.47.2554,094
148176.9.48.0/20176.9.48.1 to 176.9.63.254176.9.63.2554,094
149176.9.64.0/20176.9.64.1 to 176.9.79.254176.9.79.2554,094
150176.9.80.0/20176.9.80.1 to 176.9.95.254176.9.95.2554,094
151176.9.96.0/20176.9.96.1 to 176.9.111.254176.9.111.2554,094
152176.9.112.0/20176.9.112.1 to 176.9.127.254176.9.127.2554,094
153176.9.128.0/20176.9.128.1 to 176.9.143.254176.9.143.2554,094
154176.9.144.0/20176.9.144.1 to 176.9.159.254176.9.159.2554,094
155176.9.160.0/20176.9.160.1 to 176.9.175.254176.9.175.2554,094
156176.9.176.0/20176.9.176.1 to 176.9.191.254176.9.191.2554,094
157176.9.192.0/20176.9.192.1 to 176.9.207.254176.9.207.2554,094
158176.9.208.0/20176.9.208.1 to 176.9.223.254176.9.223.2554,094
159176.9.224.0/20176.9.224.1 to 176.9.239.254176.9.239.2554,094
160176.9.240.0/20176.9.240.1 to 176.9.255.254176.9.255.2554,094
161176.10.0.0/20176.10.0.1 to 176.10.15.254176.10.15.2554,094
162176.10.16.0/20176.10.16.1 to 176.10.31.254176.10.31.2554,094
163176.10.32.0/20176.10.32.1 to 176.10.47.254176.10.47.2554,094
164176.10.48.0/20176.10.48.1 to 176.10.63.254176.10.63.2554,094
165176.10.64.0/20176.10.64.1 to 176.10.79.254176.10.79.2554,094
166176.10.80.0/20176.10.80.1 to 176.10.95.254176.10.95.2554,094
167176.10.96.0/20176.10.96.1 to 176.10.111.254176.10.111.2554,094
168176.10.112.0/20176.10.112.1 to 176.10.127.254176.10.127.2554,094
169176.10.128.0/20176.10.128.1 to 176.10.143.254176.10.143.2554,094
170176.10.144.0/20176.10.144.1 to 176.10.159.254176.10.159.2554,094
171176.10.160.0/20176.10.160.1 to 176.10.175.254176.10.175.2554,094
172176.10.176.0/20176.10.176.1 to 176.10.191.254176.10.191.2554,094
173176.10.192.0/20176.10.192.1 to 176.10.207.254176.10.207.2554,094
174176.10.208.0/20176.10.208.1 to 176.10.223.254176.10.223.2554,094
175176.10.224.0/20176.10.224.1 to 176.10.239.254176.10.239.2554,094
176176.10.240.0/20176.10.240.1 to 176.10.255.254176.10.255.2554,094
177176.11.0.0/20176.11.0.1 to 176.11.15.254176.11.15.2554,094
178176.11.16.0/20176.11.16.1 to 176.11.31.254176.11.31.2554,094
179176.11.32.0/20176.11.32.1 to 176.11.47.254176.11.47.2554,094
180176.11.48.0/20176.11.48.1 to 176.11.63.254176.11.63.2554,094
181176.11.64.0/20176.11.64.1 to 176.11.79.254176.11.79.2554,094
182176.11.80.0/20176.11.80.1 to 176.11.95.254176.11.95.2554,094
183176.11.96.0/20176.11.96.1 to 176.11.111.254176.11.111.2554,094
184176.11.112.0/20176.11.112.1 to 176.11.127.254176.11.127.2554,094
185176.11.128.0/20176.11.128.1 to 176.11.143.254176.11.143.2554,094
186176.11.144.0/20176.11.144.1 to 176.11.159.254176.11.159.2554,094
187176.11.160.0/20176.11.160.1 to 176.11.175.254176.11.175.2554,094
188176.11.176.0/20176.11.176.1 to 176.11.191.254176.11.191.2554,094
189176.11.192.0/20176.11.192.1 to 176.11.207.254176.11.207.2554,094
190176.11.208.0/20176.11.208.1 to 176.11.223.254176.11.223.2554,094
191176.11.224.0/20176.11.224.1 to 176.11.239.254176.11.239.2554,094
192176.11.240.0/20176.11.240.1 to 176.11.255.254176.11.255.2554,094
193176.12.0.0/20176.12.0.1 to 176.12.15.254176.12.15.2554,094
194176.12.16.0/20176.12.16.1 to 176.12.31.254176.12.31.2554,094
195176.12.32.0/20176.12.32.1 to 176.12.47.254176.12.47.2554,094
196176.12.48.0/20176.12.48.1 to 176.12.63.254176.12.63.2554,094
197176.12.64.0/20176.12.64.1 to 176.12.79.254176.12.79.2554,094
198176.12.80.0/20176.12.80.1 to 176.12.95.254176.12.95.2554,094
199176.12.96.0/20176.12.96.1 to 176.12.111.254176.12.111.2554,094
200176.12.112.0/20176.12.112.1 to 176.12.127.254176.12.127.2554,094
201176.12.128.0/20176.12.128.1 to 176.12.143.254176.12.143.2554,094
202176.12.144.0/20176.12.144.1 to 176.12.159.254176.12.159.2554,094
203176.12.160.0/20176.12.160.1 to 176.12.175.254176.12.175.2554,094
204176.12.176.0/20176.12.176.1 to 176.12.191.254176.12.191.2554,094
205176.12.192.0/20176.12.192.1 to 176.12.207.254176.12.207.2554,094
206176.12.208.0/20176.12.208.1 to 176.12.223.254176.12.223.2554,094
207176.12.224.0/20176.12.224.1 to 176.12.239.254176.12.239.2554,094
208176.12.240.0/20176.12.240.1 to 176.12.255.254176.12.255.2554,094
209176.13.0.0/20176.13.0.1 to 176.13.15.254176.13.15.2554,094
210176.13.16.0/20176.13.16.1 to 176.13.31.254176.13.31.2554,094
211176.13.32.0/20176.13.32.1 to 176.13.47.254176.13.47.2554,094
212176.13.48.0/20176.13.48.1 to 176.13.63.254176.13.63.2554,094
213176.13.64.0/20176.13.64.1 to 176.13.79.254176.13.79.2554,094
214176.13.80.0/20176.13.80.1 to 176.13.95.254176.13.95.2554,094
215176.13.96.0/20176.13.96.1 to 176.13.111.254176.13.111.2554,094
216176.13.112.0/20176.13.112.1 to 176.13.127.254176.13.127.2554,094
217176.13.128.0/20176.13.128.1 to 176.13.143.254176.13.143.2554,094
218176.13.144.0/20176.13.144.1 to 176.13.159.254176.13.159.2554,094
219176.13.160.0/20176.13.160.1 to 176.13.175.254176.13.175.2554,094
220176.13.176.0/20176.13.176.1 to 176.13.191.254176.13.191.2554,094
221176.13.192.0/20176.13.192.1 to 176.13.207.254176.13.207.2554,094
222176.13.208.0/20176.13.208.1 to 176.13.223.254176.13.223.2554,094
223176.13.224.0/20176.13.224.1 to 176.13.239.254176.13.239.2554,094
224176.13.240.0/20176.13.240.1 to 176.13.255.254176.13.255.2554,094
225176.14.0.0/20176.14.0.1 to 176.14.15.254176.14.15.2554,094
226176.14.16.0/20176.14.16.1 to 176.14.31.254176.14.31.2554,094
227176.14.32.0/20176.14.32.1 to 176.14.47.254176.14.47.2554,094
228176.14.48.0/20176.14.48.1 to 176.14.63.254176.14.63.2554,094
229176.14.64.0/20176.14.64.1 to 176.14.79.254176.14.79.2554,094
230176.14.80.0/20176.14.80.1 to 176.14.95.254176.14.95.2554,094
231176.14.96.0/20176.14.96.1 to 176.14.111.254176.14.111.2554,094
232176.14.112.0/20176.14.112.1 to 176.14.127.254176.14.127.2554,094
233176.14.128.0/20176.14.128.1 to 176.14.143.254176.14.143.2554,094
234176.14.144.0/20176.14.144.1 to 176.14.159.254176.14.159.2554,094
235176.14.160.0/20176.14.160.1 to 176.14.175.254176.14.175.2554,094
236176.14.176.0/20176.14.176.1 to 176.14.191.254176.14.191.2554,094
237176.14.192.0/20176.14.192.1 to 176.14.207.254176.14.207.2554,094
238176.14.208.0/20176.14.208.1 to 176.14.223.254176.14.223.2554,094
239176.14.224.0/20176.14.224.1 to 176.14.239.254176.14.239.2554,094
240176.14.240.0/20176.14.240.1 to 176.14.255.254176.14.255.2554,094
241176.15.0.0/20176.15.0.1 to 176.15.15.254176.15.15.2554,094
242176.15.16.0/20176.15.16.1 to 176.15.31.254176.15.31.2554,094
243176.15.32.0/20176.15.32.1 to 176.15.47.254176.15.47.2554,094
244176.15.48.0/20176.15.48.1 to 176.15.63.254176.15.63.2554,094
245176.15.64.0/20176.15.64.1 to 176.15.79.254176.15.79.2554,094
246176.15.80.0/20176.15.80.1 to 176.15.95.254176.15.95.2554,094
247176.15.96.0/20176.15.96.1 to 176.15.111.254176.15.111.2554,094
248176.15.112.0/20176.15.112.1 to 176.15.127.254176.15.127.2554,094
249176.15.128.0/20176.15.128.1 to 176.15.143.254176.15.143.2554,094
250176.15.144.0/20176.15.144.1 to 176.15.159.254176.15.159.2554,094
251176.15.160.0/20176.15.160.1 to 176.15.175.254176.15.175.2554,094
252176.15.176.0/20176.15.176.1 to 176.15.191.254176.15.191.2554,094
253176.15.192.0/20176.15.192.1 to 176.15.207.254176.15.207.2554,094
254176.15.208.0/20176.15.208.1 to 176.15.223.254176.15.223.2554,094
255176.15.224.0/20176.15.224.1 to 176.15.239.254176.15.239.2554,094
256176.15.240.0/20176.15.240.1 to 176.15.255.254176.15.255.2554,094

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.