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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.

Network176.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
176.0.0.0
Broadcast address
177.255.255.255
First usable
176.0.0.1
Last usable
177.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
B (default /16)
As numbers
Hex B0000000 · Integer 2952790016 to 2986344447
Reverse DNS zones
176.in-addr.arpa
177.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10110000.00000000.00000000.00000000176.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10110000.00000000.00000000.00000000176.0.0.0
Broadcast10110001.11111111.11111111.11111111177.255.255.255
Split into smaller subnets/19
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

176.0.0.0/7 makes 4,096 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1176.0.0.0/19176.0.0.1 to 176.0.31.254176.0.31.2558,190
2176.0.32.0/19176.0.32.1 to 176.0.63.254176.0.63.2558,190
3176.0.64.0/19176.0.64.1 to 176.0.95.254176.0.95.2558,190
4176.0.96.0/19176.0.96.1 to 176.0.127.254176.0.127.2558,190
5176.0.128.0/19176.0.128.1 to 176.0.159.254176.0.159.2558,190
6176.0.160.0/19176.0.160.1 to 176.0.191.254176.0.191.2558,190
7176.0.192.0/19176.0.192.1 to 176.0.223.254176.0.223.2558,190
8176.0.224.0/19176.0.224.1 to 176.0.255.254176.0.255.2558,190
9176.1.0.0/19176.1.0.1 to 176.1.31.254176.1.31.2558,190
10176.1.32.0/19176.1.32.1 to 176.1.63.254176.1.63.2558,190
11176.1.64.0/19176.1.64.1 to 176.1.95.254176.1.95.2558,190
12176.1.96.0/19176.1.96.1 to 176.1.127.254176.1.127.2558,190
13176.1.128.0/19176.1.128.1 to 176.1.159.254176.1.159.2558,190
14176.1.160.0/19176.1.160.1 to 176.1.191.254176.1.191.2558,190
15176.1.192.0/19176.1.192.1 to 176.1.223.254176.1.223.2558,190
16176.1.224.0/19176.1.224.1 to 176.1.255.254176.1.255.2558,190
17176.2.0.0/19176.2.0.1 to 176.2.31.254176.2.31.2558,190
18176.2.32.0/19176.2.32.1 to 176.2.63.254176.2.63.2558,190
19176.2.64.0/19176.2.64.1 to 176.2.95.254176.2.95.2558,190
20176.2.96.0/19176.2.96.1 to 176.2.127.254176.2.127.2558,190
21176.2.128.0/19176.2.128.1 to 176.2.159.254176.2.159.2558,190
22176.2.160.0/19176.2.160.1 to 176.2.191.254176.2.191.2558,190
23176.2.192.0/19176.2.192.1 to 176.2.223.254176.2.223.2558,190
24176.2.224.0/19176.2.224.1 to 176.2.255.254176.2.255.2558,190
25176.3.0.0/19176.3.0.1 to 176.3.31.254176.3.31.2558,190
26176.3.32.0/19176.3.32.1 to 176.3.63.254176.3.63.2558,190
27176.3.64.0/19176.3.64.1 to 176.3.95.254176.3.95.2558,190
28176.3.96.0/19176.3.96.1 to 176.3.127.254176.3.127.2558,190
29176.3.128.0/19176.3.128.1 to 176.3.159.254176.3.159.2558,190
30176.3.160.0/19176.3.160.1 to 176.3.191.254176.3.191.2558,190
31176.3.192.0/19176.3.192.1 to 176.3.223.254176.3.223.2558,190
32176.3.224.0/19176.3.224.1 to 176.3.255.254176.3.255.2558,190
33176.4.0.0/19176.4.0.1 to 176.4.31.254176.4.31.2558,190
34176.4.32.0/19176.4.32.1 to 176.4.63.254176.4.63.2558,190
35176.4.64.0/19176.4.64.1 to 176.4.95.254176.4.95.2558,190
36176.4.96.0/19176.4.96.1 to 176.4.127.254176.4.127.2558,190
37176.4.128.0/19176.4.128.1 to 176.4.159.254176.4.159.2558,190
38176.4.160.0/19176.4.160.1 to 176.4.191.254176.4.191.2558,190
39176.4.192.0/19176.4.192.1 to 176.4.223.254176.4.223.2558,190
40176.4.224.0/19176.4.224.1 to 176.4.255.254176.4.255.2558,190
41176.5.0.0/19176.5.0.1 to 176.5.31.254176.5.31.2558,190
42176.5.32.0/19176.5.32.1 to 176.5.63.254176.5.63.2558,190
43176.5.64.0/19176.5.64.1 to 176.5.95.254176.5.95.2558,190
44176.5.96.0/19176.5.96.1 to 176.5.127.254176.5.127.2558,190
45176.5.128.0/19176.5.128.1 to 176.5.159.254176.5.159.2558,190
46176.5.160.0/19176.5.160.1 to 176.5.191.254176.5.191.2558,190
47176.5.192.0/19176.5.192.1 to 176.5.223.254176.5.223.2558,190
48176.5.224.0/19176.5.224.1 to 176.5.255.254176.5.255.2558,190
49176.6.0.0/19176.6.0.1 to 176.6.31.254176.6.31.2558,190
50176.6.32.0/19176.6.32.1 to 176.6.63.254176.6.63.2558,190
51176.6.64.0/19176.6.64.1 to 176.6.95.254176.6.95.2558,190
52176.6.96.0/19176.6.96.1 to 176.6.127.254176.6.127.2558,190
53176.6.128.0/19176.6.128.1 to 176.6.159.254176.6.159.2558,190
54176.6.160.0/19176.6.160.1 to 176.6.191.254176.6.191.2558,190
55176.6.192.0/19176.6.192.1 to 176.6.223.254176.6.223.2558,190
56176.6.224.0/19176.6.224.1 to 176.6.255.254176.6.255.2558,190
57176.7.0.0/19176.7.0.1 to 176.7.31.254176.7.31.2558,190
58176.7.32.0/19176.7.32.1 to 176.7.63.254176.7.63.2558,190
59176.7.64.0/19176.7.64.1 to 176.7.95.254176.7.95.2558,190
60176.7.96.0/19176.7.96.1 to 176.7.127.254176.7.127.2558,190
61176.7.128.0/19176.7.128.1 to 176.7.159.254176.7.159.2558,190
62176.7.160.0/19176.7.160.1 to 176.7.191.254176.7.191.2558,190
63176.7.192.0/19176.7.192.1 to 176.7.223.254176.7.223.2558,190
64176.7.224.0/19176.7.224.1 to 176.7.255.254176.7.255.2558,190
65176.8.0.0/19176.8.0.1 to 176.8.31.254176.8.31.2558,190
66176.8.32.0/19176.8.32.1 to 176.8.63.254176.8.63.2558,190
67176.8.64.0/19176.8.64.1 to 176.8.95.254176.8.95.2558,190
68176.8.96.0/19176.8.96.1 to 176.8.127.254176.8.127.2558,190
69176.8.128.0/19176.8.128.1 to 176.8.159.254176.8.159.2558,190
70176.8.160.0/19176.8.160.1 to 176.8.191.254176.8.191.2558,190
71176.8.192.0/19176.8.192.1 to 176.8.223.254176.8.223.2558,190
72176.8.224.0/19176.8.224.1 to 176.8.255.254176.8.255.2558,190
73176.9.0.0/19176.9.0.1 to 176.9.31.254176.9.31.2558,190
74176.9.32.0/19176.9.32.1 to 176.9.63.254176.9.63.2558,190
75176.9.64.0/19176.9.64.1 to 176.9.95.254176.9.95.2558,190
76176.9.96.0/19176.9.96.1 to 176.9.127.254176.9.127.2558,190
77176.9.128.0/19176.9.128.1 to 176.9.159.254176.9.159.2558,190
78176.9.160.0/19176.9.160.1 to 176.9.191.254176.9.191.2558,190
79176.9.192.0/19176.9.192.1 to 176.9.223.254176.9.223.2558,190
80176.9.224.0/19176.9.224.1 to 176.9.255.254176.9.255.2558,190
81176.10.0.0/19176.10.0.1 to 176.10.31.254176.10.31.2558,190
82176.10.32.0/19176.10.32.1 to 176.10.63.254176.10.63.2558,190
83176.10.64.0/19176.10.64.1 to 176.10.95.254176.10.95.2558,190
84176.10.96.0/19176.10.96.1 to 176.10.127.254176.10.127.2558,190
85176.10.128.0/19176.10.128.1 to 176.10.159.254176.10.159.2558,190
86176.10.160.0/19176.10.160.1 to 176.10.191.254176.10.191.2558,190
87176.10.192.0/19176.10.192.1 to 176.10.223.254176.10.223.2558,190
88176.10.224.0/19176.10.224.1 to 176.10.255.254176.10.255.2558,190
89176.11.0.0/19176.11.0.1 to 176.11.31.254176.11.31.2558,190
90176.11.32.0/19176.11.32.1 to 176.11.63.254176.11.63.2558,190
91176.11.64.0/19176.11.64.1 to 176.11.95.254176.11.95.2558,190
92176.11.96.0/19176.11.96.1 to 176.11.127.254176.11.127.2558,190
93176.11.128.0/19176.11.128.1 to 176.11.159.254176.11.159.2558,190
94176.11.160.0/19176.11.160.1 to 176.11.191.254176.11.191.2558,190
95176.11.192.0/19176.11.192.1 to 176.11.223.254176.11.223.2558,190
96176.11.224.0/19176.11.224.1 to 176.11.255.254176.11.255.2558,190
97176.12.0.0/19176.12.0.1 to 176.12.31.254176.12.31.2558,190
98176.12.32.0/19176.12.32.1 to 176.12.63.254176.12.63.2558,190
99176.12.64.0/19176.12.64.1 to 176.12.95.254176.12.95.2558,190
100176.12.96.0/19176.12.96.1 to 176.12.127.254176.12.127.2558,190
101176.12.128.0/19176.12.128.1 to 176.12.159.254176.12.159.2558,190
102176.12.160.0/19176.12.160.1 to 176.12.191.254176.12.191.2558,190
103176.12.192.0/19176.12.192.1 to 176.12.223.254176.12.223.2558,190
104176.12.224.0/19176.12.224.1 to 176.12.255.254176.12.255.2558,190
105176.13.0.0/19176.13.0.1 to 176.13.31.254176.13.31.2558,190
106176.13.32.0/19176.13.32.1 to 176.13.63.254176.13.63.2558,190
107176.13.64.0/19176.13.64.1 to 176.13.95.254176.13.95.2558,190
108176.13.96.0/19176.13.96.1 to 176.13.127.254176.13.127.2558,190
109176.13.128.0/19176.13.128.1 to 176.13.159.254176.13.159.2558,190
110176.13.160.0/19176.13.160.1 to 176.13.191.254176.13.191.2558,190
111176.13.192.0/19176.13.192.1 to 176.13.223.254176.13.223.2558,190
112176.13.224.0/19176.13.224.1 to 176.13.255.254176.13.255.2558,190
113176.14.0.0/19176.14.0.1 to 176.14.31.254176.14.31.2558,190
114176.14.32.0/19176.14.32.1 to 176.14.63.254176.14.63.2558,190
115176.14.64.0/19176.14.64.1 to 176.14.95.254176.14.95.2558,190
116176.14.96.0/19176.14.96.1 to 176.14.127.254176.14.127.2558,190
117176.14.128.0/19176.14.128.1 to 176.14.159.254176.14.159.2558,190
118176.14.160.0/19176.14.160.1 to 176.14.191.254176.14.191.2558,190
119176.14.192.0/19176.14.192.1 to 176.14.223.254176.14.223.2558,190
120176.14.224.0/19176.14.224.1 to 176.14.255.254176.14.255.2558,190
121176.15.0.0/19176.15.0.1 to 176.15.31.254176.15.31.2558,190
122176.15.32.0/19176.15.32.1 to 176.15.63.254176.15.63.2558,190
123176.15.64.0/19176.15.64.1 to 176.15.95.254176.15.95.2558,190
124176.15.96.0/19176.15.96.1 to 176.15.127.254176.15.127.2558,190
125176.15.128.0/19176.15.128.1 to 176.15.159.254176.15.159.2558,190
126176.15.160.0/19176.15.160.1 to 176.15.191.254176.15.191.2558,190
127176.15.192.0/19176.15.192.1 to 176.15.223.254176.15.223.2558,190
128176.15.224.0/19176.15.224.1 to 176.15.255.254176.15.255.2558,190
129176.16.0.0/19176.16.0.1 to 176.16.31.254176.16.31.2558,190
130176.16.32.0/19176.16.32.1 to 176.16.63.254176.16.63.2558,190
131176.16.64.0/19176.16.64.1 to 176.16.95.254176.16.95.2558,190
132176.16.96.0/19176.16.96.1 to 176.16.127.254176.16.127.2558,190
133176.16.128.0/19176.16.128.1 to 176.16.159.254176.16.159.2558,190
134176.16.160.0/19176.16.160.1 to 176.16.191.254176.16.191.2558,190
135176.16.192.0/19176.16.192.1 to 176.16.223.254176.16.223.2558,190
136176.16.224.0/19176.16.224.1 to 176.16.255.254176.16.255.2558,190
137176.17.0.0/19176.17.0.1 to 176.17.31.254176.17.31.2558,190
138176.17.32.0/19176.17.32.1 to 176.17.63.254176.17.63.2558,190
139176.17.64.0/19176.17.64.1 to 176.17.95.254176.17.95.2558,190
140176.17.96.0/19176.17.96.1 to 176.17.127.254176.17.127.2558,190
141176.17.128.0/19176.17.128.1 to 176.17.159.254176.17.159.2558,190
142176.17.160.0/19176.17.160.1 to 176.17.191.254176.17.191.2558,190
143176.17.192.0/19176.17.192.1 to 176.17.223.254176.17.223.2558,190
144176.17.224.0/19176.17.224.1 to 176.17.255.254176.17.255.2558,190
145176.18.0.0/19176.18.0.1 to 176.18.31.254176.18.31.2558,190
146176.18.32.0/19176.18.32.1 to 176.18.63.254176.18.63.2558,190
147176.18.64.0/19176.18.64.1 to 176.18.95.254176.18.95.2558,190
148176.18.96.0/19176.18.96.1 to 176.18.127.254176.18.127.2558,190
149176.18.128.0/19176.18.128.1 to 176.18.159.254176.18.159.2558,190
150176.18.160.0/19176.18.160.1 to 176.18.191.254176.18.191.2558,190
151176.18.192.0/19176.18.192.1 to 176.18.223.254176.18.223.2558,190
152176.18.224.0/19176.18.224.1 to 176.18.255.254176.18.255.2558,190
153176.19.0.0/19176.19.0.1 to 176.19.31.254176.19.31.2558,190
154176.19.32.0/19176.19.32.1 to 176.19.63.254176.19.63.2558,190
155176.19.64.0/19176.19.64.1 to 176.19.95.254176.19.95.2558,190
156176.19.96.0/19176.19.96.1 to 176.19.127.254176.19.127.2558,190
157176.19.128.0/19176.19.128.1 to 176.19.159.254176.19.159.2558,190
158176.19.160.0/19176.19.160.1 to 176.19.191.254176.19.191.2558,190
159176.19.192.0/19176.19.192.1 to 176.19.223.254176.19.223.2558,190
160176.19.224.0/19176.19.224.1 to 176.19.255.254176.19.255.2558,190
161176.20.0.0/19176.20.0.1 to 176.20.31.254176.20.31.2558,190
162176.20.32.0/19176.20.32.1 to 176.20.63.254176.20.63.2558,190
163176.20.64.0/19176.20.64.1 to 176.20.95.254176.20.95.2558,190
164176.20.96.0/19176.20.96.1 to 176.20.127.254176.20.127.2558,190
165176.20.128.0/19176.20.128.1 to 176.20.159.254176.20.159.2558,190
166176.20.160.0/19176.20.160.1 to 176.20.191.254176.20.191.2558,190
167176.20.192.0/19176.20.192.1 to 176.20.223.254176.20.223.2558,190
168176.20.224.0/19176.20.224.1 to 176.20.255.254176.20.255.2558,190
169176.21.0.0/19176.21.0.1 to 176.21.31.254176.21.31.2558,190
170176.21.32.0/19176.21.32.1 to 176.21.63.254176.21.63.2558,190
171176.21.64.0/19176.21.64.1 to 176.21.95.254176.21.95.2558,190
172176.21.96.0/19176.21.96.1 to 176.21.127.254176.21.127.2558,190
173176.21.128.0/19176.21.128.1 to 176.21.159.254176.21.159.2558,190
174176.21.160.0/19176.21.160.1 to 176.21.191.254176.21.191.2558,190
175176.21.192.0/19176.21.192.1 to 176.21.223.254176.21.223.2558,190
176176.21.224.0/19176.21.224.1 to 176.21.255.254176.21.255.2558,190
177176.22.0.0/19176.22.0.1 to 176.22.31.254176.22.31.2558,190
178176.22.32.0/19176.22.32.1 to 176.22.63.254176.22.63.2558,190
179176.22.64.0/19176.22.64.1 to 176.22.95.254176.22.95.2558,190
180176.22.96.0/19176.22.96.1 to 176.22.127.254176.22.127.2558,190
181176.22.128.0/19176.22.128.1 to 176.22.159.254176.22.159.2558,190
182176.22.160.0/19176.22.160.1 to 176.22.191.254176.22.191.2558,190
183176.22.192.0/19176.22.192.1 to 176.22.223.254176.22.223.2558,190
184176.22.224.0/19176.22.224.1 to 176.22.255.254176.22.255.2558,190
185176.23.0.0/19176.23.0.1 to 176.23.31.254176.23.31.2558,190
186176.23.32.0/19176.23.32.1 to 176.23.63.254176.23.63.2558,190
187176.23.64.0/19176.23.64.1 to 176.23.95.254176.23.95.2558,190
188176.23.96.0/19176.23.96.1 to 176.23.127.254176.23.127.2558,190
189176.23.128.0/19176.23.128.1 to 176.23.159.254176.23.159.2558,190
190176.23.160.0/19176.23.160.1 to 176.23.191.254176.23.191.2558,190
191176.23.192.0/19176.23.192.1 to 176.23.223.254176.23.223.2558,190
192176.23.224.0/19176.23.224.1 to 176.23.255.254176.23.255.2558,190
193176.24.0.0/19176.24.0.1 to 176.24.31.254176.24.31.2558,190
194176.24.32.0/19176.24.32.1 to 176.24.63.254176.24.63.2558,190
195176.24.64.0/19176.24.64.1 to 176.24.95.254176.24.95.2558,190
196176.24.96.0/19176.24.96.1 to 176.24.127.254176.24.127.2558,190
197176.24.128.0/19176.24.128.1 to 176.24.159.254176.24.159.2558,190
198176.24.160.0/19176.24.160.1 to 176.24.191.254176.24.191.2558,190
199176.24.192.0/19176.24.192.1 to 176.24.223.254176.24.223.2558,190
200176.24.224.0/19176.24.224.1 to 176.24.255.254176.24.255.2558,190
201176.25.0.0/19176.25.0.1 to 176.25.31.254176.25.31.2558,190
202176.25.32.0/19176.25.32.1 to 176.25.63.254176.25.63.2558,190
203176.25.64.0/19176.25.64.1 to 176.25.95.254176.25.95.2558,190
204176.25.96.0/19176.25.96.1 to 176.25.127.254176.25.127.2558,190
205176.25.128.0/19176.25.128.1 to 176.25.159.254176.25.159.2558,190
206176.25.160.0/19176.25.160.1 to 176.25.191.254176.25.191.2558,190
207176.25.192.0/19176.25.192.1 to 176.25.223.254176.25.223.2558,190
208176.25.224.0/19176.25.224.1 to 176.25.255.254176.25.255.2558,190
209176.26.0.0/19176.26.0.1 to 176.26.31.254176.26.31.2558,190
210176.26.32.0/19176.26.32.1 to 176.26.63.254176.26.63.2558,190
211176.26.64.0/19176.26.64.1 to 176.26.95.254176.26.95.2558,190
212176.26.96.0/19176.26.96.1 to 176.26.127.254176.26.127.2558,190
213176.26.128.0/19176.26.128.1 to 176.26.159.254176.26.159.2558,190
214176.26.160.0/19176.26.160.1 to 176.26.191.254176.26.191.2558,190
215176.26.192.0/19176.26.192.1 to 176.26.223.254176.26.223.2558,190
216176.26.224.0/19176.26.224.1 to 176.26.255.254176.26.255.2558,190
217176.27.0.0/19176.27.0.1 to 176.27.31.254176.27.31.2558,190
218176.27.32.0/19176.27.32.1 to 176.27.63.254176.27.63.2558,190
219176.27.64.0/19176.27.64.1 to 176.27.95.254176.27.95.2558,190
220176.27.96.0/19176.27.96.1 to 176.27.127.254176.27.127.2558,190
221176.27.128.0/19176.27.128.1 to 176.27.159.254176.27.159.2558,190
222176.27.160.0/19176.27.160.1 to 176.27.191.254176.27.191.2558,190
223176.27.192.0/19176.27.192.1 to 176.27.223.254176.27.223.2558,190
224176.27.224.0/19176.27.224.1 to 176.27.255.254176.27.255.2558,190
225176.28.0.0/19176.28.0.1 to 176.28.31.254176.28.31.2558,190
226176.28.32.0/19176.28.32.1 to 176.28.63.254176.28.63.2558,190
227176.28.64.0/19176.28.64.1 to 176.28.95.254176.28.95.2558,190
228176.28.96.0/19176.28.96.1 to 176.28.127.254176.28.127.2558,190
229176.28.128.0/19176.28.128.1 to 176.28.159.254176.28.159.2558,190
230176.28.160.0/19176.28.160.1 to 176.28.191.254176.28.191.2558,190
231176.28.192.0/19176.28.192.1 to 176.28.223.254176.28.223.2558,190
232176.28.224.0/19176.28.224.1 to 176.28.255.254176.28.255.2558,190
233176.29.0.0/19176.29.0.1 to 176.29.31.254176.29.31.2558,190
234176.29.32.0/19176.29.32.1 to 176.29.63.254176.29.63.2558,190
235176.29.64.0/19176.29.64.1 to 176.29.95.254176.29.95.2558,190
236176.29.96.0/19176.29.96.1 to 176.29.127.254176.29.127.2558,190
237176.29.128.0/19176.29.128.1 to 176.29.159.254176.29.159.2558,190
238176.29.160.0/19176.29.160.1 to 176.29.191.254176.29.191.2558,190
239176.29.192.0/19176.29.192.1 to 176.29.223.254176.29.223.2558,190
240176.29.224.0/19176.29.224.1 to 176.29.255.254176.29.255.2558,190
241176.30.0.0/19176.30.0.1 to 176.30.31.254176.30.31.2558,190
242176.30.32.0/19176.30.32.1 to 176.30.63.254176.30.63.2558,190
243176.30.64.0/19176.30.64.1 to 176.30.95.254176.30.95.2558,190
244176.30.96.0/19176.30.96.1 to 176.30.127.254176.30.127.2558,190
245176.30.128.0/19176.30.128.1 to 176.30.159.254176.30.159.2558,190
246176.30.160.0/19176.30.160.1 to 176.30.191.254176.30.191.2558,190
247176.30.192.0/19176.30.192.1 to 176.30.223.254176.30.223.2558,190
248176.30.224.0/19176.30.224.1 to 176.30.255.254176.30.255.2558,190
249176.31.0.0/19176.31.0.1 to 176.31.31.254176.31.31.2558,190
250176.31.32.0/19176.31.32.1 to 176.31.63.254176.31.63.2558,190
251176.31.64.0/19176.31.64.1 to 176.31.95.254176.31.95.2558,190
252176.31.96.0/19176.31.96.1 to 176.31.127.254176.31.127.2558,190
253176.31.128.0/19176.31.128.1 to 176.31.159.254176.31.159.2558,190
254176.31.160.0/19176.31.160.1 to 176.31.191.254176.31.191.2558,190
255176.31.192.0/19176.31.192.1 to 176.31.223.254176.31.223.2558,190
256176.31.224.0/19176.31.224.1 to 176.31.255.254176.31.255.2558,190

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.