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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/18
/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 2,048 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1176.0.0.0/18176.0.0.1 to 176.0.63.254176.0.63.25516,382
2176.0.64.0/18176.0.64.1 to 176.0.127.254176.0.127.25516,382
3176.0.128.0/18176.0.128.1 to 176.0.191.254176.0.191.25516,382
4176.0.192.0/18176.0.192.1 to 176.0.255.254176.0.255.25516,382
5176.1.0.0/18176.1.0.1 to 176.1.63.254176.1.63.25516,382
6176.1.64.0/18176.1.64.1 to 176.1.127.254176.1.127.25516,382
7176.1.128.0/18176.1.128.1 to 176.1.191.254176.1.191.25516,382
8176.1.192.0/18176.1.192.1 to 176.1.255.254176.1.255.25516,382
9176.2.0.0/18176.2.0.1 to 176.2.63.254176.2.63.25516,382
10176.2.64.0/18176.2.64.1 to 176.2.127.254176.2.127.25516,382
11176.2.128.0/18176.2.128.1 to 176.2.191.254176.2.191.25516,382
12176.2.192.0/18176.2.192.1 to 176.2.255.254176.2.255.25516,382
13176.3.0.0/18176.3.0.1 to 176.3.63.254176.3.63.25516,382
14176.3.64.0/18176.3.64.1 to 176.3.127.254176.3.127.25516,382
15176.3.128.0/18176.3.128.1 to 176.3.191.254176.3.191.25516,382
16176.3.192.0/18176.3.192.1 to 176.3.255.254176.3.255.25516,382
17176.4.0.0/18176.4.0.1 to 176.4.63.254176.4.63.25516,382
18176.4.64.0/18176.4.64.1 to 176.4.127.254176.4.127.25516,382
19176.4.128.0/18176.4.128.1 to 176.4.191.254176.4.191.25516,382
20176.4.192.0/18176.4.192.1 to 176.4.255.254176.4.255.25516,382
21176.5.0.0/18176.5.0.1 to 176.5.63.254176.5.63.25516,382
22176.5.64.0/18176.5.64.1 to 176.5.127.254176.5.127.25516,382
23176.5.128.0/18176.5.128.1 to 176.5.191.254176.5.191.25516,382
24176.5.192.0/18176.5.192.1 to 176.5.255.254176.5.255.25516,382
25176.6.0.0/18176.6.0.1 to 176.6.63.254176.6.63.25516,382
26176.6.64.0/18176.6.64.1 to 176.6.127.254176.6.127.25516,382
27176.6.128.0/18176.6.128.1 to 176.6.191.254176.6.191.25516,382
28176.6.192.0/18176.6.192.1 to 176.6.255.254176.6.255.25516,382
29176.7.0.0/18176.7.0.1 to 176.7.63.254176.7.63.25516,382
30176.7.64.0/18176.7.64.1 to 176.7.127.254176.7.127.25516,382
31176.7.128.0/18176.7.128.1 to 176.7.191.254176.7.191.25516,382
32176.7.192.0/18176.7.192.1 to 176.7.255.254176.7.255.25516,382
33176.8.0.0/18176.8.0.1 to 176.8.63.254176.8.63.25516,382
34176.8.64.0/18176.8.64.1 to 176.8.127.254176.8.127.25516,382
35176.8.128.0/18176.8.128.1 to 176.8.191.254176.8.191.25516,382
36176.8.192.0/18176.8.192.1 to 176.8.255.254176.8.255.25516,382
37176.9.0.0/18176.9.0.1 to 176.9.63.254176.9.63.25516,382
38176.9.64.0/18176.9.64.1 to 176.9.127.254176.9.127.25516,382
39176.9.128.0/18176.9.128.1 to 176.9.191.254176.9.191.25516,382
40176.9.192.0/18176.9.192.1 to 176.9.255.254176.9.255.25516,382
41176.10.0.0/18176.10.0.1 to 176.10.63.254176.10.63.25516,382
42176.10.64.0/18176.10.64.1 to 176.10.127.254176.10.127.25516,382
43176.10.128.0/18176.10.128.1 to 176.10.191.254176.10.191.25516,382
44176.10.192.0/18176.10.192.1 to 176.10.255.254176.10.255.25516,382
45176.11.0.0/18176.11.0.1 to 176.11.63.254176.11.63.25516,382
46176.11.64.0/18176.11.64.1 to 176.11.127.254176.11.127.25516,382
47176.11.128.0/18176.11.128.1 to 176.11.191.254176.11.191.25516,382
48176.11.192.0/18176.11.192.1 to 176.11.255.254176.11.255.25516,382
49176.12.0.0/18176.12.0.1 to 176.12.63.254176.12.63.25516,382
50176.12.64.0/18176.12.64.1 to 176.12.127.254176.12.127.25516,382
51176.12.128.0/18176.12.128.1 to 176.12.191.254176.12.191.25516,382
52176.12.192.0/18176.12.192.1 to 176.12.255.254176.12.255.25516,382
53176.13.0.0/18176.13.0.1 to 176.13.63.254176.13.63.25516,382
54176.13.64.0/18176.13.64.1 to 176.13.127.254176.13.127.25516,382
55176.13.128.0/18176.13.128.1 to 176.13.191.254176.13.191.25516,382
56176.13.192.0/18176.13.192.1 to 176.13.255.254176.13.255.25516,382
57176.14.0.0/18176.14.0.1 to 176.14.63.254176.14.63.25516,382
58176.14.64.0/18176.14.64.1 to 176.14.127.254176.14.127.25516,382
59176.14.128.0/18176.14.128.1 to 176.14.191.254176.14.191.25516,382
60176.14.192.0/18176.14.192.1 to 176.14.255.254176.14.255.25516,382
61176.15.0.0/18176.15.0.1 to 176.15.63.254176.15.63.25516,382
62176.15.64.0/18176.15.64.1 to 176.15.127.254176.15.127.25516,382
63176.15.128.0/18176.15.128.1 to 176.15.191.254176.15.191.25516,382
64176.15.192.0/18176.15.192.1 to 176.15.255.254176.15.255.25516,382
65176.16.0.0/18176.16.0.1 to 176.16.63.254176.16.63.25516,382
66176.16.64.0/18176.16.64.1 to 176.16.127.254176.16.127.25516,382
67176.16.128.0/18176.16.128.1 to 176.16.191.254176.16.191.25516,382
68176.16.192.0/18176.16.192.1 to 176.16.255.254176.16.255.25516,382
69176.17.0.0/18176.17.0.1 to 176.17.63.254176.17.63.25516,382
70176.17.64.0/18176.17.64.1 to 176.17.127.254176.17.127.25516,382
71176.17.128.0/18176.17.128.1 to 176.17.191.254176.17.191.25516,382
72176.17.192.0/18176.17.192.1 to 176.17.255.254176.17.255.25516,382
73176.18.0.0/18176.18.0.1 to 176.18.63.254176.18.63.25516,382
74176.18.64.0/18176.18.64.1 to 176.18.127.254176.18.127.25516,382
75176.18.128.0/18176.18.128.1 to 176.18.191.254176.18.191.25516,382
76176.18.192.0/18176.18.192.1 to 176.18.255.254176.18.255.25516,382
77176.19.0.0/18176.19.0.1 to 176.19.63.254176.19.63.25516,382
78176.19.64.0/18176.19.64.1 to 176.19.127.254176.19.127.25516,382
79176.19.128.0/18176.19.128.1 to 176.19.191.254176.19.191.25516,382
80176.19.192.0/18176.19.192.1 to 176.19.255.254176.19.255.25516,382
81176.20.0.0/18176.20.0.1 to 176.20.63.254176.20.63.25516,382
82176.20.64.0/18176.20.64.1 to 176.20.127.254176.20.127.25516,382
83176.20.128.0/18176.20.128.1 to 176.20.191.254176.20.191.25516,382
84176.20.192.0/18176.20.192.1 to 176.20.255.254176.20.255.25516,382
85176.21.0.0/18176.21.0.1 to 176.21.63.254176.21.63.25516,382
86176.21.64.0/18176.21.64.1 to 176.21.127.254176.21.127.25516,382
87176.21.128.0/18176.21.128.1 to 176.21.191.254176.21.191.25516,382
88176.21.192.0/18176.21.192.1 to 176.21.255.254176.21.255.25516,382
89176.22.0.0/18176.22.0.1 to 176.22.63.254176.22.63.25516,382
90176.22.64.0/18176.22.64.1 to 176.22.127.254176.22.127.25516,382
91176.22.128.0/18176.22.128.1 to 176.22.191.254176.22.191.25516,382
92176.22.192.0/18176.22.192.1 to 176.22.255.254176.22.255.25516,382
93176.23.0.0/18176.23.0.1 to 176.23.63.254176.23.63.25516,382
94176.23.64.0/18176.23.64.1 to 176.23.127.254176.23.127.25516,382
95176.23.128.0/18176.23.128.1 to 176.23.191.254176.23.191.25516,382
96176.23.192.0/18176.23.192.1 to 176.23.255.254176.23.255.25516,382
97176.24.0.0/18176.24.0.1 to 176.24.63.254176.24.63.25516,382
98176.24.64.0/18176.24.64.1 to 176.24.127.254176.24.127.25516,382
99176.24.128.0/18176.24.128.1 to 176.24.191.254176.24.191.25516,382
100176.24.192.0/18176.24.192.1 to 176.24.255.254176.24.255.25516,382
101176.25.0.0/18176.25.0.1 to 176.25.63.254176.25.63.25516,382
102176.25.64.0/18176.25.64.1 to 176.25.127.254176.25.127.25516,382
103176.25.128.0/18176.25.128.1 to 176.25.191.254176.25.191.25516,382
104176.25.192.0/18176.25.192.1 to 176.25.255.254176.25.255.25516,382
105176.26.0.0/18176.26.0.1 to 176.26.63.254176.26.63.25516,382
106176.26.64.0/18176.26.64.1 to 176.26.127.254176.26.127.25516,382
107176.26.128.0/18176.26.128.1 to 176.26.191.254176.26.191.25516,382
108176.26.192.0/18176.26.192.1 to 176.26.255.254176.26.255.25516,382
109176.27.0.0/18176.27.0.1 to 176.27.63.254176.27.63.25516,382
110176.27.64.0/18176.27.64.1 to 176.27.127.254176.27.127.25516,382
111176.27.128.0/18176.27.128.1 to 176.27.191.254176.27.191.25516,382
112176.27.192.0/18176.27.192.1 to 176.27.255.254176.27.255.25516,382
113176.28.0.0/18176.28.0.1 to 176.28.63.254176.28.63.25516,382
114176.28.64.0/18176.28.64.1 to 176.28.127.254176.28.127.25516,382
115176.28.128.0/18176.28.128.1 to 176.28.191.254176.28.191.25516,382
116176.28.192.0/18176.28.192.1 to 176.28.255.254176.28.255.25516,382
117176.29.0.0/18176.29.0.1 to 176.29.63.254176.29.63.25516,382
118176.29.64.0/18176.29.64.1 to 176.29.127.254176.29.127.25516,382
119176.29.128.0/18176.29.128.1 to 176.29.191.254176.29.191.25516,382
120176.29.192.0/18176.29.192.1 to 176.29.255.254176.29.255.25516,382
121176.30.0.0/18176.30.0.1 to 176.30.63.254176.30.63.25516,382
122176.30.64.0/18176.30.64.1 to 176.30.127.254176.30.127.25516,382
123176.30.128.0/18176.30.128.1 to 176.30.191.254176.30.191.25516,382
124176.30.192.0/18176.30.192.1 to 176.30.255.254176.30.255.25516,382
125176.31.0.0/18176.31.0.1 to 176.31.63.254176.31.63.25516,382
126176.31.64.0/18176.31.64.1 to 176.31.127.254176.31.127.25516,382
127176.31.128.0/18176.31.128.1 to 176.31.191.254176.31.191.25516,382
128176.31.192.0/18176.31.192.1 to 176.31.255.254176.31.255.25516,382
129176.32.0.0/18176.32.0.1 to 176.32.63.254176.32.63.25516,382
130176.32.64.0/18176.32.64.1 to 176.32.127.254176.32.127.25516,382
131176.32.128.0/18176.32.128.1 to 176.32.191.254176.32.191.25516,382
132176.32.192.0/18176.32.192.1 to 176.32.255.254176.32.255.25516,382
133176.33.0.0/18176.33.0.1 to 176.33.63.254176.33.63.25516,382
134176.33.64.0/18176.33.64.1 to 176.33.127.254176.33.127.25516,382
135176.33.128.0/18176.33.128.1 to 176.33.191.254176.33.191.25516,382
136176.33.192.0/18176.33.192.1 to 176.33.255.254176.33.255.25516,382
137176.34.0.0/18176.34.0.1 to 176.34.63.254176.34.63.25516,382
138176.34.64.0/18176.34.64.1 to 176.34.127.254176.34.127.25516,382
139176.34.128.0/18176.34.128.1 to 176.34.191.254176.34.191.25516,382
140176.34.192.0/18176.34.192.1 to 176.34.255.254176.34.255.25516,382
141176.35.0.0/18176.35.0.1 to 176.35.63.254176.35.63.25516,382
142176.35.64.0/18176.35.64.1 to 176.35.127.254176.35.127.25516,382
143176.35.128.0/18176.35.128.1 to 176.35.191.254176.35.191.25516,382
144176.35.192.0/18176.35.192.1 to 176.35.255.254176.35.255.25516,382
145176.36.0.0/18176.36.0.1 to 176.36.63.254176.36.63.25516,382
146176.36.64.0/18176.36.64.1 to 176.36.127.254176.36.127.25516,382
147176.36.128.0/18176.36.128.1 to 176.36.191.254176.36.191.25516,382
148176.36.192.0/18176.36.192.1 to 176.36.255.254176.36.255.25516,382
149176.37.0.0/18176.37.0.1 to 176.37.63.254176.37.63.25516,382
150176.37.64.0/18176.37.64.1 to 176.37.127.254176.37.127.25516,382
151176.37.128.0/18176.37.128.1 to 176.37.191.254176.37.191.25516,382
152176.37.192.0/18176.37.192.1 to 176.37.255.254176.37.255.25516,382
153176.38.0.0/18176.38.0.1 to 176.38.63.254176.38.63.25516,382
154176.38.64.0/18176.38.64.1 to 176.38.127.254176.38.127.25516,382
155176.38.128.0/18176.38.128.1 to 176.38.191.254176.38.191.25516,382
156176.38.192.0/18176.38.192.1 to 176.38.255.254176.38.255.25516,382
157176.39.0.0/18176.39.0.1 to 176.39.63.254176.39.63.25516,382
158176.39.64.0/18176.39.64.1 to 176.39.127.254176.39.127.25516,382
159176.39.128.0/18176.39.128.1 to 176.39.191.254176.39.191.25516,382
160176.39.192.0/18176.39.192.1 to 176.39.255.254176.39.255.25516,382
161176.40.0.0/18176.40.0.1 to 176.40.63.254176.40.63.25516,382
162176.40.64.0/18176.40.64.1 to 176.40.127.254176.40.127.25516,382
163176.40.128.0/18176.40.128.1 to 176.40.191.254176.40.191.25516,382
164176.40.192.0/18176.40.192.1 to 176.40.255.254176.40.255.25516,382
165176.41.0.0/18176.41.0.1 to 176.41.63.254176.41.63.25516,382
166176.41.64.0/18176.41.64.1 to 176.41.127.254176.41.127.25516,382
167176.41.128.0/18176.41.128.1 to 176.41.191.254176.41.191.25516,382
168176.41.192.0/18176.41.192.1 to 176.41.255.254176.41.255.25516,382
169176.42.0.0/18176.42.0.1 to 176.42.63.254176.42.63.25516,382
170176.42.64.0/18176.42.64.1 to 176.42.127.254176.42.127.25516,382
171176.42.128.0/18176.42.128.1 to 176.42.191.254176.42.191.25516,382
172176.42.192.0/18176.42.192.1 to 176.42.255.254176.42.255.25516,382
173176.43.0.0/18176.43.0.1 to 176.43.63.254176.43.63.25516,382
174176.43.64.0/18176.43.64.1 to 176.43.127.254176.43.127.25516,382
175176.43.128.0/18176.43.128.1 to 176.43.191.254176.43.191.25516,382
176176.43.192.0/18176.43.192.1 to 176.43.255.254176.43.255.25516,382
177176.44.0.0/18176.44.0.1 to 176.44.63.254176.44.63.25516,382
178176.44.64.0/18176.44.64.1 to 176.44.127.254176.44.127.25516,382
179176.44.128.0/18176.44.128.1 to 176.44.191.254176.44.191.25516,382
180176.44.192.0/18176.44.192.1 to 176.44.255.254176.44.255.25516,382
181176.45.0.0/18176.45.0.1 to 176.45.63.254176.45.63.25516,382
182176.45.64.0/18176.45.64.1 to 176.45.127.254176.45.127.25516,382
183176.45.128.0/18176.45.128.1 to 176.45.191.254176.45.191.25516,382
184176.45.192.0/18176.45.192.1 to 176.45.255.254176.45.255.25516,382
185176.46.0.0/18176.46.0.1 to 176.46.63.254176.46.63.25516,382
186176.46.64.0/18176.46.64.1 to 176.46.127.254176.46.127.25516,382
187176.46.128.0/18176.46.128.1 to 176.46.191.254176.46.191.25516,382
188176.46.192.0/18176.46.192.1 to 176.46.255.254176.46.255.25516,382
189176.47.0.0/18176.47.0.1 to 176.47.63.254176.47.63.25516,382
190176.47.64.0/18176.47.64.1 to 176.47.127.254176.47.127.25516,382
191176.47.128.0/18176.47.128.1 to 176.47.191.254176.47.191.25516,382
192176.47.192.0/18176.47.192.1 to 176.47.255.254176.47.255.25516,382
193176.48.0.0/18176.48.0.1 to 176.48.63.254176.48.63.25516,382
194176.48.64.0/18176.48.64.1 to 176.48.127.254176.48.127.25516,382
195176.48.128.0/18176.48.128.1 to 176.48.191.254176.48.191.25516,382
196176.48.192.0/18176.48.192.1 to 176.48.255.254176.48.255.25516,382
197176.49.0.0/18176.49.0.1 to 176.49.63.254176.49.63.25516,382
198176.49.64.0/18176.49.64.1 to 176.49.127.254176.49.127.25516,382
199176.49.128.0/18176.49.128.1 to 176.49.191.254176.49.191.25516,382
200176.49.192.0/18176.49.192.1 to 176.49.255.254176.49.255.25516,382
201176.50.0.0/18176.50.0.1 to 176.50.63.254176.50.63.25516,382
202176.50.64.0/18176.50.64.1 to 176.50.127.254176.50.127.25516,382
203176.50.128.0/18176.50.128.1 to 176.50.191.254176.50.191.25516,382
204176.50.192.0/18176.50.192.1 to 176.50.255.254176.50.255.25516,382
205176.51.0.0/18176.51.0.1 to 176.51.63.254176.51.63.25516,382
206176.51.64.0/18176.51.64.1 to 176.51.127.254176.51.127.25516,382
207176.51.128.0/18176.51.128.1 to 176.51.191.254176.51.191.25516,382
208176.51.192.0/18176.51.192.1 to 176.51.255.254176.51.255.25516,382
209176.52.0.0/18176.52.0.1 to 176.52.63.254176.52.63.25516,382
210176.52.64.0/18176.52.64.1 to 176.52.127.254176.52.127.25516,382
211176.52.128.0/18176.52.128.1 to 176.52.191.254176.52.191.25516,382
212176.52.192.0/18176.52.192.1 to 176.52.255.254176.52.255.25516,382
213176.53.0.0/18176.53.0.1 to 176.53.63.254176.53.63.25516,382
214176.53.64.0/18176.53.64.1 to 176.53.127.254176.53.127.25516,382
215176.53.128.0/18176.53.128.1 to 176.53.191.254176.53.191.25516,382
216176.53.192.0/18176.53.192.1 to 176.53.255.254176.53.255.25516,382
217176.54.0.0/18176.54.0.1 to 176.54.63.254176.54.63.25516,382
218176.54.64.0/18176.54.64.1 to 176.54.127.254176.54.127.25516,382
219176.54.128.0/18176.54.128.1 to 176.54.191.254176.54.191.25516,382
220176.54.192.0/18176.54.192.1 to 176.54.255.254176.54.255.25516,382
221176.55.0.0/18176.55.0.1 to 176.55.63.254176.55.63.25516,382
222176.55.64.0/18176.55.64.1 to 176.55.127.254176.55.127.25516,382
223176.55.128.0/18176.55.128.1 to 176.55.191.254176.55.191.25516,382
224176.55.192.0/18176.55.192.1 to 176.55.255.254176.55.255.25516,382
225176.56.0.0/18176.56.0.1 to 176.56.63.254176.56.63.25516,382
226176.56.64.0/18176.56.64.1 to 176.56.127.254176.56.127.25516,382
227176.56.128.0/18176.56.128.1 to 176.56.191.254176.56.191.25516,382
228176.56.192.0/18176.56.192.1 to 176.56.255.254176.56.255.25516,382
229176.57.0.0/18176.57.0.1 to 176.57.63.254176.57.63.25516,382
230176.57.64.0/18176.57.64.1 to 176.57.127.254176.57.127.25516,382
231176.57.128.0/18176.57.128.1 to 176.57.191.254176.57.191.25516,382
232176.57.192.0/18176.57.192.1 to 176.57.255.254176.57.255.25516,382
233176.58.0.0/18176.58.0.1 to 176.58.63.254176.58.63.25516,382
234176.58.64.0/18176.58.64.1 to 176.58.127.254176.58.127.25516,382
235176.58.128.0/18176.58.128.1 to 176.58.191.254176.58.191.25516,382
236176.58.192.0/18176.58.192.1 to 176.58.255.254176.58.255.25516,382
237176.59.0.0/18176.59.0.1 to 176.59.63.254176.59.63.25516,382
238176.59.64.0/18176.59.64.1 to 176.59.127.254176.59.127.25516,382
239176.59.128.0/18176.59.128.1 to 176.59.191.254176.59.191.25516,382
240176.59.192.0/18176.59.192.1 to 176.59.255.254176.59.255.25516,382
241176.60.0.0/18176.60.0.1 to 176.60.63.254176.60.63.25516,382
242176.60.64.0/18176.60.64.1 to 176.60.127.254176.60.127.25516,382
243176.60.128.0/18176.60.128.1 to 176.60.191.254176.60.191.25516,382
244176.60.192.0/18176.60.192.1 to 176.60.255.254176.60.255.25516,382
245176.61.0.0/18176.61.0.1 to 176.61.63.254176.61.63.25516,382
246176.61.64.0/18176.61.64.1 to 176.61.127.254176.61.127.25516,382
247176.61.128.0/18176.61.128.1 to 176.61.191.254176.61.191.25516,382
248176.61.192.0/18176.61.192.1 to 176.61.255.254176.61.255.25516,382
249176.62.0.0/18176.62.0.1 to 176.62.63.254176.62.63.25516,382
250176.62.64.0/18176.62.64.1 to 176.62.127.254176.62.127.25516,382
251176.62.128.0/18176.62.128.1 to 176.62.191.254176.62.191.25516,382
252176.62.192.0/18176.62.192.1 to 176.62.255.254176.62.255.25516,382
253176.63.0.0/18176.63.0.1 to 176.63.63.254176.63.63.25516,382
254176.63.64.0/18176.63.64.1 to 176.63.127.254176.63.127.25516,382
255176.63.128.0/18176.63.128.1 to 176.63.191.254176.63.191.25516,382
256176.63.192.0/18176.63.192.1 to 176.63.255.254176.63.255.25516,382

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.